Helping out: short tasks

Would you like to help out at a PR, differently from reviewing? Here are some ideas:

take a look at PRs with just some mathlib-infrastructure-related CI failure: unless it's an infrastructure PR, these are spurious/not the PRs fault. If the failure is spurious, commenting to this effect can be helpful.
take a look at PRs labelled help-wanted or please-adopt
If the author hasn't noticed, you can ask in a PR which just has a merge conflict, but would be reviewable otherwise. (Remember, that most contributors to mathlib are volunteers, contribute in their free time and often have other commitments — and that real-life events can happen!)
check if any 'stale' PR by a new contributor benefits from support, such as help with failing CI or providing feedback on the code
check if any 'stale' delegated PR benefits from support, such as by fixing merge conflicts (but be sure to ask first; the PR author might simply be very busy)

This dashboard was last updated on: March 04, 2026 at 21:47 UTC

PRs with just failing CI, but only often-spurious jobs

There are currently no PRs with just an infrastructure-related CI failure. Congratulations!

PRs looking for help

Number	Author	Title	Description	Labels	+/-	Modified files (first 100)	📝	💬	All users who commented or reviewed	Assignee(s)	Updated	Last status change	total time in review
9642	eric-wieser author:eric-wieser	refactor(Analysis/Normed/{Group/Field}/Basic): Let `extends` generate the repeated fields	New-style structure shenanigans mean that instance constructors randomly complain about a missing field that can be found with `__ : MetricSpace _ := infer_instance`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) I will write a longer PR description for this once CI is happy	help-wanted WIP awaiting-author merge-conflict t-analysis	122/202	Mathlib/Analysis/Calculus/ContDiff/Basic.lean,Mathlib/Analysis/Complex/Basic.lean,Mathlib/Analysis/Matrix.lean,Mathlib/Analysis/Normed/Field/Basic.lean,Mathlib/Analysis/Normed/Group/Basic.lean,Mathlib/Analysis/Normed/Group/Completion.lean,Mathlib/Analysis/Normed/Order/Basic.lean,Mathlib/Analysis/NormedSpace/ProdLp.lean,Mathlib/Analysis/NormedSpace/Star/Matrix.lean,Mathlib/Analysis/NormedSpace/Unitization.lean,Mathlib/Analysis/Quaternion.lean,Mathlib/Geometry/Manifold/Instances/Sphere.lean,Mathlib/InformationTheory/Hamming.lean,Mathlib/MeasureTheory/Measure/Lebesgue/VolumeOfBalls.lean,Mathlib/NumberTheory/NumberField/CanonicalEmbedding.lean,Mathlib/NumberTheory/Padics/PadicIntegers.lean,Mathlib/Topology/ContinuousFunction/Bounded.lean	17	11	['eric-wieser', 'leanprover-bot', 'urkud']	nobody	581-48794 1 year ago	759-28696 2 years ago	0-0 0 seconds
6791	eric-wieser author:eric-wieser	refactor: Use flat structures for morphisms	This restores the symmetry we had in Lean3, where we had `MonoidHom.mk f one mul` not `MonoidHom.mk (OneHom.mk f one) mul`, and `f.toFun` wasn't notation for `f.toMulHom.toFun`. The nesting provided by the previous inheritance is useless to us in the face of `MonoidHomClass.toMonoidHom`, which completely eta-expands the structure anyway. We call the class `FunLikeFlatHack._` because this means the field is called `to_` which uses up less space in the goal view than any alternative. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted awaiting-author merge-conflict awaiting-CI	174/201	Mathlib/Algebra/Algebra/Equiv.lean,Mathlib/Algebra/Algebra/Hom.lean,Mathlib/Algebra/Category/GroupCat/ZModuleEquivalence.lean,Mathlib/Algebra/Category/GroupWithZeroCat.lean,Mathlib/Algebra/Category/ModuleCat/Presheaf.lean,Mathlib/Algebra/Category/MonCat/Basic.lean,Mathlib/Algebra/Group/Ext.lean,Mathlib/Algebra/Group/Prod.lean,Mathlib/Algebra/Group/UniqueProds.lean,Mathlib/Algebra/Hom/Equiv/Basic.lean,Mathlib/Algebra/Hom/Group/Defs.lean,Mathlib/Algebra/Hom/GroupAction.lean,Mathlib/Algebra/Hom/NonUnitalAlg.lean,Mathlib/Algebra/Hom/Ring/Defs.lean,Mathlib/Algebra/Lie/Basic.lean,Mathlib/Algebra/Module/Equiv.lean,Mathlib/Algebra/Module/LinearMap.lean,Mathlib/Algebra/Order/Hom/Ring.lean,Mathlib/Algebra/Order/Interval.lean,Mathlib/Algebra/Ring/Equiv.lean,Mathlib/Analysis/Normed/Group/SemiNormedGroupCat.lean,Mathlib/Data/FunLike/Basic.lean,Mathlib/Data/Rat/Cast/CharZero.lean,Mathlib/Data/Real/EReal.lean,Mathlib/Data/Real/Sqrt.lean,Mathlib/GroupTheory/FreeAbelianGroup.lean,Mathlib/GroupTheory/MonoidLocalization.lean,Mathlib/LinearAlgebra/Quotient.lean,Mathlib/LinearAlgebra/TensorProduct.lean,Mathlib/RingTheory/RingInvo.lean,Mathlib/Topology/Algebra/Module/Basic.lean,Mathlib/Topology/MetricSpace/Dilation.lean	32	0	[]	nobody	581-48793 1 year ago	898-16653 2 years ago	0-0 0 seconds
6931	urkud author:urkud	refactor(Analysis/Normed): use `RingHomIsometric` for `.norm_cast`	--- I don't understand why linter fails. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted merge-conflict t-analysis	78/68	Mathlib/Analysis/LocallyConvex/ContinuousOfBounded.lean,Mathlib/Analysis/Normed/Field/Basic.lean,Mathlib/Analysis/Normed/Group/Basic.lean,Mathlib/Analysis/NormedSpace/Basic.lean,Mathlib/Analysis/NormedSpace/Exponential.lean,Mathlib/Analysis/NormedSpace/Spectrum.lean,Mathlib/Analysis/RCLike/Basic.lean,Mathlib/NumberTheory/NumberField/Embeddings.lean	8	0	[]	nobody	581-48793 1 year ago	603-29497 1 year ago	0-0 0 seconds
7903	urkud author:urkud	feat: define `UnboundedSpace`	--- The new instances generate some timeouts, and I don't understand why. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted merge-conflict t-topology	111/59	Mathlib/Analysis/BoxIntegral/Basic.lean,Mathlib/Analysis/Normed/Module/Basic.lean,Mathlib/Topology/Bornology/Basic.lean,Mathlib/Topology/Bornology/Constructions.lean,Mathlib/Topology/MetricSpace/Bounded.lean,Mathlib/Topology/MetricSpace/GromovHausdorffRealized.lean	6	1	['github-actions']	nobody	574-36770 1 year ago	574-36770 1 year ago	0-0 0 seconds
9444	erdOne author:erdOne	feat: Various instances regarding `𝓞 K`.	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted merge-conflict t-number-theory	27/0	Mathlib/NumberTheory/NumberField/Basic.lean,Mathlib/RingTheory/IntegralClosure.lean	2	9	['erdOne', 'leanprover-bot', 'mattrobball', 'riccardobrasca', 'xroblot']	nobody	566-38546 1 year ago	566-38546 1 year ago	0-0 0 seconds
11837	trivial1711 author:trivial1711	feat: completion of a uniform multiplicative group	Multiplicativize `Topology.Algebra.GroupCompletion`. That is, rewrite it in the multiplicative setting and recover the original results using `@[to_additive]`. - Because `@[to_additive]` doesn't work with `noncomputable section` (https://github.com/leanprover/lean4/pull/2610), some instances with `@[to_additive]` need to be explicitly marked with `noncomputable instance`. - One might be tempted to multiplicativize this definition from `Topology.Algebra.GroupCompletion`: ```lean instance [UniformSpace α] [Add α] : Add (Completion α) := ⟨Completion.map₂ (· + ·)⟩ ``` to this: ```lean @[to_additive] instance [UniformSpace α] [Mul α] : Mul (Completion α) := ⟨Completion.map₂ (· * ·)⟩ ``` However, as Eric Wieser pointed out, doing so would create a bad diamond with the definition ```lean instance [UniformSpace α] [TopologicalRing α] [UniformAddGroup α] [Ring α] : Mul (Completion α) := ⟨curry <\| (denseInducing_coe.prod denseInducing_coe).extend ((↑) ∘ uncurry (· * ·))⟩ ``` in `Topology.Algebra.UniformRing`. How should this diamond be resolved? Well, the definition of multiplication that uses `curry <\| (denseInducing_coe.prod denseInducing_coe).extend ((↑) ∘ uncurry (· * ·))` is the "correct" one. For example, it yields the correct result if `α` is `ℚ`, unlike the definition that uses `Completion.map₂ (· * ·)`. (This is because `Completion.map₂` yields junk values if used on a function which is not uniformly continuous. Note, however, that if multiplication on `α` is uniformly continuous, then `Completion.map₂ (· * ·)` and `curry <\| (denseInducing_coe.prod denseInducing_coe).extend ((↑) ∘ uncurry (· * ·))` are propositionally equal.) So, following Eric's suggestion, we remove the definition that uses `Completion.map₂ (· * ·)`, and generalize the other definition to any uniform space with a multiplication operation: ```lean @[to_additive] noncomputable instance [UniformSpace α] [Mul α] : Mul (Completion α) := ⟨curry <\| (denseInducing_coe.prod denseInducing_coe).extend ((↑) ∘ uncurry (· * ·))⟩ ``` This requires slightly modifying some of the proofs in `Topology.Algebra.GroupCompletion`. For example, suppose that `α` is a uniform group. Since we can no longer use `Completion.continuous_map₂`, it becomes more efficient to prove that the multiplication, inversion, and division operations on `Completion α` are uniformly continuous before we prove that `Completion α` is a group. - Previously, `Topology.Algebra.GroupCompletion` had an instance: ```lean instance [UniformSpace α] [Sub α] : Sub (Completion α) := ... ``` Naively multiplicativizing this would yield ```lean @[to_additive] instance [UniformSpace α] [Inv α] : Inv (Completion α) := ... ``` Unfortunately, this would conflict with `Topology.Algebra.UniformField`, which already instantiates `Inv (Completion α)` when `α` is a uniform field. Instead, we use two different `instance` declarations. (If `α` is an additive group, then this instantiates `Neg (Completion α)` twice, and the instances are syntactically equal.) ```lean @[to_additive] noncomputable instance [UniformSpace α] [Group α] : Inv (Completion α) := ... instance [UniformSpace α] [Neg α] : Neg (Completion α) := ... ``` This avoids the bad diamond (because a uniform field can never be a `Group`) while remaining backward compatible. Note that the `@[to_additive]` is necessary here, because it maintains the link between the additive setting and multiplicative setting. We use a similar method to instantiate `Div (Completion α)`. - Some definitions in this file involve a module structure on `α`. We leave these as is and do not attempt to multiplicativize them at all. - The instance of `DistribMulAction` must be multiplicativized to an instance of `MulDistribMulAction` manually. Zulip thread: https://leanprover.zulipchat.com/#narrow/stream/287929-mathlib4/topic/Completion.20of.20a.20uniform.20multiplicative.20group --- # (Small) Issue Recall the following trick that this pull request uses to define inversion and negation on uniform spaces. The idea is that we define negation on the completion of any uniform space that has a negation operation, but we define inversion on only the completion of a uniform space that has the structure of a multiplicative group. We do this to avoid creating a bad diamond with the inversion operation on a uniform field. ```lean @[to_additive] noncomputable instance {α : Type} [UniformSpace α] [Group α] : Inv (Completion α) := ... instance {α : Type} [UniformSpace α] [Neg α] : Neg (Completion α) := ... ``` Now, suppose that we want to prove `coe_inv_of_group` (resp. `coe_neg`), which states that the coercion `α → Completion α` commutes with inversion (resp. negation). In the current version of this pull request, `coe_inv_of_group` (resp. `coe_neg`) only applies to uniform multiplicative (resp. additive) groups. However, we do not use the fact that multiplication (resp. addition) on `α` is uniformly continuous to prove it. We only use the fact that inversion (resp. negation) is continuous. So, what we really want is to have more general statements that look like this: ```lean theorem coe_inv_of_group {α : Type} [UniformSpace α] [Group α] [ContinuousInv α] : ... theorem coe_neg {α : Type} [UniformSpace α] [Neg α] [ContinuousNeg α] : ... ``` Note that `coe_inv_of_group` needs the assumption `[Group α]`, because otherwise inversion is not defined on `Completion α` at all. However, `coe_neg` does not need the analogous assumption `[AdditiveGroup α]`. The question is: If `coe_inv_of_group` and `coe_neg` are written in this more general form, how can we link them using `@[to_additive]`? Here is one option, but it obviously leaves something to be desired. ```lean @[to_additive coe_neg_do_not_use_this_use_the_more_general_version] theorem coe_inv_of_group {α : Type} [UniformSpace α] [Group α] [ContinuousInv α] : ... theorem coe_neg {α : Type} [UniformSpace α] [Neg α] [ContinuousNeg α] : ... ``` Co-authored-by: Eric Wieser --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted WIP merge-conflict t-topology t-algebra label:t-algebra$	342/217	Mathlib/Analysis/InnerProductSpace/Completion.lean,Mathlib/Analysis/Normed/Group/HomCompletion.lean,Mathlib/Analysis/Normed/Module/Completion.lean,Mathlib/Topology/Algebra/GroupCompletion.lean,Mathlib/Topology/Algebra/InfiniteSum/GroupCompletion.lean,Mathlib/Topology/Algebra/Nonarchimedean/Completion.lean,Mathlib/Topology/Algebra/UniformField.lean,Mathlib/Topology/Algebra/UniformMulAction.lean,Mathlib/Topology/Algebra/UniformRing.lean	9	14	['eric-wieser', 'github-actions', 'trivial1711']	nobody	398-3991 1 year ago	398-3991 1 year ago	0-0 0 seconds
15115	kkytola author:kkytola	feat: Generalize assumptions in liminf and limsup results in ENNReals	In a [review comment](https://github.com/leanprover-community/mathlib4/pull/13938#discussion_r1649744441) it was pointed out that results about liminf and limsup in ENNReal hold under milder assumptions. This PR does the generalization. --- This PR is split off from #13938, where the review comment was made. The changes needed for the suggested generalization were of different kind than the simple PR's content, justifying a separate PR. - [x] depends on: #13938 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted awaiting-author merge-conflict t-topology t-order	215/27	Mathlib/MeasureTheory/Measure/Portmanteau.lean,Mathlib/Order/LiminfLimsup.lean,Mathlib/Topology/Instances/ENNReal.lean	3	8	['Ruben-VandeVelde', 'github-actions', 'grunweg', 'j-loreaux', 'kkytola', 'leanprover-community-mathlib4-bot']	nobody	293-31846 9 months ago	318-16150 10 months ago	0-0 0 seconds
22925	ggranberry author:ggranberry	feat(Mathlib/PlaceHolder/ToeplitzHausdorff): Toeplitz-Hausdorff	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted WIP awaiting-author t-analysis new-contributor will-close-soon	411/0	Mathlib/PlaceHolder/ToeplitzHausdorff.lean,Mathlib/PlaceHolder/ToeplitzHausdorff_v2.lean	2	11	['faenuccio', 'ggranberry', 'github-actions']	faenuccio assignee:faenuccio	203-38842 6 months ago	203-39045 6 months ago	0-0 0 seconds
7300	ah1112 author:ah1112	feat: synthetic geometry	This is adding synthetic geometry using Avigad's axioms and formalizing Euclid Book I, through the Pythagorean theorem. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted awaiting-author merge-conflict t-euclidean-geometry	2661/0	Mathlib.lean,Mathlib/Geometry/Synthetic/Avigad/Axioms.lean,Mathlib/Geometry/Synthetic/Avigad/EuclidBookI.lean,Mathlib/Geometry/Synthetic/Avigad/Tactics.lean	4	74	['ah1112', 'alreadydone', 'eric-wieser', 'github-actions', 'leanprover-community-bot-assistant', 'plp127', 'tb65536', 'urkud']	nobody	194-71607 6 months ago	224-20165 7 months ago	0-0 0 seconds
5863	eric-wieser author:eric-wieser	feat: add elaborators for concrete matrices	--- - [x] depends on: #5866 - [ ] depends on: #5897 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted blocked-by-other-PR merge-conflict t-meta	257/7	Mathlib/Control/Monad/Cont.lean,Mathlib/Data/Matrix/Auto.lean,MathlibTest/matrix_auto.lean	3	8	['eric-wieser', 'github-actions', 'kim-em', 'leanprover-community-bot-assistant', 'mathlib4-merge-conflict-bot']	nobody	105-51639 3 months ago	105-51640 3 months ago	0-0 0 seconds
5919	MithicSpirit author:MithicSpirit	feat: implement orthogonality for AffineSubspace	Define `AffineSubspace.orthogonal` and `AffineSubspace.IsOrtho`, as well as develop an API emulating that of `Submodule.orthogonal` and `Submodule.IsOrtho`, respectively. Additionally, provide some relevant lemmas exclusive to affine subspaces, which are mostly to do with the relationship between orthogonality and `AffineSubspace.Parallel`. Closes #5539 --- Still WIP as I need to add more docstrings as well as notations for the new definitions. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted WIP merge-conflict t-analysis new-contributor	287/0	Mathlib.lean,Mathlib/Analysis/InnerProductSpace/AffineSubspace.lean	2	7	['MithicSpirit', 'eric-wieser', 'github-actions', 'leanprover-community-bot-assistant', 'mathlib4-merge-conflict-bot']	MithicSpirit assignee:MithicSpirit	105-51638 3 months ago	105-51638 3 months ago	0-0 0 seconds
13442	dignissimus author:dignissimus	feat: mabel tactic for multiplicative abelian groups	Mabel tactic for multiplicative abelian groups (#10361) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted awaiting-author modifies-tactic-syntax merge-conflict t-meta new-contributor	439/0	Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/MAbel.lean,MathlibTest/mabel.lean	4	11	['BoltonBailey', 'dignissimus', 'github-actions', 'joneugster', 'kbuzzard', 'mathlib4-merge-conflict-bot']	joneugster assignee:joneugster	105-51374 3 months ago	105-51375 3 months ago	0-0 0 seconds
29675	yury-harmonic author:yury-harmonic	feat(Wolstenholme): new file	Co-authored-by: @Aristotle-Harmonic --- I still need to cleanup the proof and write the docs. For now, it's just what the AI generated, forward-ported to the latest Mathlib. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted awaiting-author merge-conflict t-data	198/0	Mathlib.lean,Mathlib/Data/Nat/Choose/Wolstenholme.lean	2	4	['github-actions', 'mathlib4-merge-conflict-bot', 'yury-harmonic']	nobody	105-49026 3 months ago	105-49027 3 months ago	0-125 2 minutes
6859	MohanadAhmed author:MohanadAhmed	feat: TryLean4Bundle: Windows Bundle Creator	# `TryLean4Bundle`: Windows Bundle Creator A Windows batch script and a CI yml file that create an self extracting archive. The user should 1. just download the archive, 2. double click the archive to expand 3. double click the `RunLean.bat` script in the expanded archive. The script currently downloads 7 dependencies into CI then unpacks them in the appropriate locations and finally packs them back. To try a bundle created using these scripts but from a different repo see (https://github.com/MohanadAhmed/TryLean4Bundle/releases) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted WIP CI	114/0	.github/workflows/mk_windows_bundle.yml,scripts/windowsBundle.bat	2	0	[]	nobody	105-22951 3 months ago	917-78064 2 years ago	0-0 0 seconds
5934	eric-wieser author:eric-wieser	feat: port Data.Rat.MetaDefs	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) This needs some eyes from people familiar with Qq	help-wanted mathlib-port merge-conflict t-meta	183/0	Mathlib.lean,Mathlib/Data/Rat/MetaDefs.lean,test/rat.lean	3	5	['eric-wieser', 'gebner', 'vihdzp']	nobody	68-10277 2 months ago	751-35781 2 years ago	0-0 0 seconds
26349	mans0954 author:mans0954	feat(Analysis/SpecialFunctions/Trigonometric/Basic): sin and cos of multiples of π / 3	This PR continues the work from #25009. Original PR: https://github.com/leanprover-community/mathlib4/pull/25009	help-wanted please-adopt t-analysis	159/0	Mathlib/Algebra/Order/Monoid/NatCast.lean,Mathlib/Analysis/SpecialFunctions/Trigonometric/Basic.lean,Mathlib/Data/Nat/Cast/Defs.lean,MathlibTest/trigonometry.lean	4	3	['github-actions', 'mans0954', 'themathqueen']	nobody	52-76116 1 month ago	52-76116 1 month ago	5-42837 5 days
12934	grunweg author:grunweg	chore: replace more uses of > or ≥ by < or ≤	These were flagged by the linter in https://github.com/leanprover-community/mathlib4/pull/12879: it is easy to simple avoid > or ≥ in hypotheses or haves. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted awaiting-author merge-conflict	41/42	Archive/Imo/Imo1962Q1.lean,Archive/Imo/Imo1988Q6.lean,Archive/Imo/Imo1994Q1.lean,Archive/Imo/Imo2005Q3.lean,Archive/Imo/Imo2006Q3.lean,Archive/Imo/Imo2008Q2.lean,Archive/Imo/Imo2008Q3.lean,Archive/Imo/Imo2019Q4.lean,Archive/Sensitivity.lean,Archive/Wiedijk100Theorems/CubingACube.lean,Mathlib/Tactic/Linarith/Datatypes.lean,test/cancel_denoms.lean,test/congr.lean,test/interval_cases.lean,test/observe.lean	15	12	['YaelDillies', 'adomani', 'github-actions', 'grunweg', 'jcommelin', 'urkud']	nobody	51-63088 1 month ago	594-58394 1 year ago	0-0 0 seconds

PRs with just a merge conflict

Number	Author	Title	Description	Labels	+/-	Modified files (first 100)	📝	💬	All users who commented or reviewed	Assignee(s)	Updated	Last status change	total time in review
8788	FMLJohn author:FMLJohn	feat(Algebra/Module/GradeZeroModule): if `A` is a graded semiring and `M` is a graded `A`-module, then each grade of `M` is a module over the 0-th grade of `A`.	--- - [ ] depends on: #8187 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	237/4	Mathlib.lean,Mathlib/Algebra/DirectSum/Internal.lean,Mathlib/Algebra/GradedMonoid.lean,Mathlib/Algebra/Module/GradeZeroModule.lean,Mathlib/RingTheory/GradedAlgebra/Basic.lean,Mathlib/RingTheory/GradedAlgebra/Noetherian.lean	6	4	['FMLJohn', 'github-actions', 'leanprover-community-mathlib4-bot']	nobody	581-48794 1 year ago	615-36696 1 year ago	0-0 0 seconds
6777	adomani author:adomani	chore(CovariantClass): replace eta-expanded (· ·), (· + ·), (· ≤ ·), (· < ·)	Replace `CovariantClass X X (· * ·) (· ≤ ·)` with -> `CovariantClass X X HMul.hMul LE.le` and similarly for `HAdd`, `LT`, `Contravariant`. This PR is inspired by [Issue #6646](https://github.com/leanprover-community/mathlib4/issues/6646) and, more specifically, [this comment](https://github.com/leanprover-community/mathlib4/issues/6646#issuecomment-1692792066). Note that https://github.com/leanprover/lean4/pull/2267 would make this unnecessary --- ```bash # First sed command: # the first captured pattern is `CovariantClass ` # the second captured pattern is `` # the third captured pattern is `+` or `` # the fourth captured pattern is `<` or `≤` # a match for `CovariantClass (· ·) (· ·)` becomes # `CovariantClass replaceop replaceop` # Second sed command: similar to the first, but looks for `(Function.swap (· ·))` sed -i ' s=$Co[ntra]variantClass \(..$ \2 \)(· $[+]$ ·) (· $[<≤]$ ·)=\1replaceop\3 replaceop\4=g s=$Co[ntra]variantClass \(..$ \2 \)($[Functio\.swap ]$(· $[+]$ ·)) (· $[<≤]$ ·)=\1(\3replaceop\4) replaceop\5=g s=replaceop+=HAdd.hAdd=g s=replaceop\=HMul.hMul=g s=replaceop<=LT.lt=g s=replaceop≤=LE.le=g s=$Co[ntra]variantClass N N$ (· \ ·) r=\1 HMul.hMul r=g s=$Co[ntra]variantClass N N (swap μ)$ (· ≤ ·)=\1 LE.le=g s=$Co[ntra]variantClass N N$ (swap (· \* ·)) r=\1 (swap HMul.hMul) r=g s=$CovariantClass (Filter α) (Filter α)$ (· / ·) (· ≤ ·)=\1 HDiv.hDiv LE.le=g s=$CovariantClass (Filter α) (Filter α)$ (swap (· / ·)) (· ≤ ·)=\1 (swap HDiv.hDiv) LE.le=g s=$Co[ntra]variantClass . (fun x y .> . \* .)$ (· ≤ ·)=\1 LE.le=g s=$Co[ntra]variantClass . (fun x y .> . \* .)$ (· < ·)=\1 LT.lt=g s=$Co[ntra]variantClass [^}]$ (· ≤ ·)=\1 LE.le=g s=$CovariantClass .* (Filter β)$ (· • ·) LE.le=\1 HSMul.hSMul LE.le=g ' $(git ls-files '*.lean') ``` [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict	703/678	Counterexamples/ZeroDivisorsInAddMonoidAlgebras.lean,Mathlib/Algebra/BigOperators/Basic.lean,Mathlib/Algebra/Bounds.lean,Mathlib/Algebra/CovariantAndContravariant.lean,Mathlib/Algebra/DirectSum/Internal.lean,Mathlib/Algebra/Group/UniqueProds.lean,Mathlib/Algebra/GroupPower/Order.lean,Mathlib/Algebra/MonoidAlgebra/Degree.lean,Mathlib/Algebra/Order/Archimedean.lean,Mathlib/Algebra/Order/Group/Abs.lean,Mathlib/Algebra/Order/Group/Defs.lean,Mathlib/Algebra/Order/Group/DenselyOrdered.lean,Mathlib/Algebra/Order/Group/MinMax.lean,Mathlib/Algebra/Order/Group/OrderIso.lean,Mathlib/Algebra/Order/Hom/Monoid.lean,Mathlib/Algebra/Order/Interval.lean,Mathlib/Algebra/Order/Kleene.lean,Mathlib/Algebra/Order/LatticeGroup.lean,Mathlib/Algebra/Order/Module.lean,Mathlib/Algebra/Order/Monoid/Basic.lean,Mathlib/Algebra/Order/Monoid/Cancel/Defs.lean,Mathlib/Algebra/Order/Monoid/Canonical/Defs.lean,Mathlib/Algebra/Order/Monoid/Defs.lean,Mathlib/Algebra/Order/Monoid/Lemmas.lean,Mathlib/Algebra/Order/Monoid/MinMax.lean,Mathlib/Algebra/Order/Monoid/NatCast.lean,Mathlib/Algebra/Order/Monoid/OrderDual.lean,Mathlib/Algebra/Order/Monoid/Prod.lean,Mathlib/Algebra/Order/Monoid/WithTop.lean,Mathlib/Algebra/Order/Monoid/WithZero/Basic.lean,Mathlib/Algebra/Order/Monoid/WithZero/Defs.lean,Mathlib/Algebra/Order/Nonneg/Ring.lean,Mathlib/Algebra/Order/Pointwise.lean,Mathlib/Algebra/Order/Positive/Ring.lean,Mathlib/Algebra/Order/Ring/Canonical.lean,Mathlib/Algebra/Order/Ring/Defs.lean,Mathlib/Algebra/Order/Ring/Lemmas.lean,Mathlib/Algebra/Order/Sub/Basic.lean,Mathlib/Algebra/Order/Sub/Canonical.lean,Mathlib/Algebra/Order/Sub/Defs.lean,Mathlib/Algebra/Order/WithZero.lean,Mathlib/Algebra/Parity.lean,Mathlib/Algebra/Star/Order.lean,Mathlib/Algebra/Tropical/Basic.lean,Mathlib/Analysis/Normed/Order/Lattice.lean,Mathlib/Data/DFinsupp/Lex.lean,Mathlib/Data/DFinsupp/Order.lean,Mathlib/Data/Finset/Fold.lean,Mathlib/Data/Finsupp/Lex.lean,Mathlib/Data/Finsupp/Order.lean,Mathlib/Data/List/BigOperators/Basic.lean,Mathlib/Data/List/BigOperators/Lemmas.lean,Mathlib/Data/Multiset/Basic.lean,Mathlib/Data/Nat/Cast/Order.lean,Mathlib/Data/PNat/Basic.lean,Mathlib/Data/Real/ENNReal.lean,Mathlib/Data/Real/NNReal.lean,Mathlib/Data/Set/Semiring.lean,Mathlib/Data/Sign.lean,Mathlib/MeasureTheory/Function/LpOrder.lean,Mathlib/MeasureTheory/Function/SimpleFuncDenseLp.lean,Mathlib/MeasureTheory/Measure/MeasureSpace.lean,Mathlib/MeasureTheory/Measure/VectorMeasure.lean,Mathlib/Order/ConditionallyCompleteLattice/Group.lean,Mathlib/Order/Filter/Basic.lean,Mathlib/Order/Filter/Pointwise.lean,Mathlib/Probability/Martingale/Basic.lean,Mathlib/Probability/Process/Stopping.lean,Mathlib/RingTheory/GradedAlgebra/Basic.lean,Mathlib/SetTheory/Cardinal/Basic.lean,Mathlib/SetTheory/Game/Basic.lean,Mathlib/SetTheory/Game/PGame.lean,Mathlib/SetTheory/Ordinal/Arithmetic.lean,Mathlib/SetTheory/Ordinal/Basic.lean,Mathlib/SetTheory/Ordinal/NaturalOps.lean,Mathlib/Tactic/GCongr/Core.lean,Mathlib/Tactic/Positivity/Basic.lean,Mathlib/Topology/ContinuousFunction/Algebra.lean,lean-toolchain,test/Recall.lean,test/propose.lean	81	36	['adomani', 'alreadydone', 'digama0', 'eric-wieser', 'ericrbg', 'jcommelin', 'leanprover-bot', 'sgouezel']	nobody	581-48793 1 year ago	603-29497 1 year ago	0-0 0 seconds
6491	eric-wieser author:eric-wieser	chore(Mathlib/Algebra/Hom/GroupAction): add `SMulHomClass.comp_smul`	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	24/10	Mathlib/Algebra/Hom/GroupAction.lean	1	0	[]	nobody	581-48792 1 year ago	603-29497 1 year ago	0-0 0 seconds
10629	madvorak author:madvorak	feat: List.cons_sublist_append_iff_right	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-data	11/0	Mathlib/Data/List/Basic.lean	1	1	['eric-wieser']	nobody	567-42337 1 year ago	567-42337 1 year ago	0-0 0 seconds
13791	digama0 author:digama0	refactor: Primrec and Partrec	General cleanup of the `Primrec` and `Partrec` files, to better adjust to lean 4 things. The main user-visible change is that `Primrec₂` is no longer a `def` but an `abbrev`, because it was causing inference issues in lean 4. I also removed all the nonterminal `simp`s in `PartrecCode.lean`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-computability tech debt	585/778	Mathlib/Computability/Ackermann.lean,Mathlib/Computability/Halting.lean,Mathlib/Computability/Partrec.lean,Mathlib/Computability/PartrecCode.lean,Mathlib/Computability/Primrec.lean	5	2	['github-actions', 'grunweg']	nobody	563-5182 1 year ago	603-29497 1 year ago	0-0 0 seconds
11964	adamtopaz author:adamtopaz	feat: The functor of points of a scheme	We construct the functor of points functor, and prove that it's full and faithful. --- - [ ] depends on: #11947 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-category-theory t-algebraic-geometry	210/0	Mathlib.lean,Mathlib/AlgebraicGeometry/FunctorOfPoints.lean,Mathlib/AlgebraicGeometry/OpenImmersion.lean	3	4	['github-actions', 'grunweg', 'leanprover-community-mathlib4-bot']	nobody	563-5041 1 year ago	603-29497 1 year ago	0-0 0 seconds
12418	rosborn author:rosborn	style: replace preimage_val with ↓∩ notation	--- This is a rough draft of what the new `↓∩` notation would look like within mathlib. I believe this is an improvement in clarity and would like to have `↓∩` as a standard notation (along with `''`, `⁻¹'`, `↑`, etc...). As `↓∩` is specialized for `Set`s, I have only changed `preimage_val` when the left-hand side of `↓∩` is a `Set`. The introduction of the `↓∩` notation to Data.Set.Image is temporary as it isn't possible to import Data.Set.Subset directly. If we want `↓∩` unscoped, where would be the best place to define it? An option is Data.Set.Defs, but the notation cannot be defined without additional imports as the file does not import `notation3`. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict	56/61	Mathlib/Analysis/InnerProductSpace/Projection.lean,Mathlib/Data/Set/Function.lean,Mathlib/Data/Set/Image.lean,Mathlib/Data/Set/Subset.lean,Mathlib/MeasureTheory/Constructions/Polish.lean,Mathlib/MeasureTheory/MeasurableSpace/Basic.lean,Mathlib/MeasureTheory/Measure/Restrict.lean,Mathlib/Order/UpperLower/Basic.lean,Mathlib/Topology/Bases.lean,Mathlib/Topology/Clopen.lean,Mathlib/Topology/Connected/Basic.lean,Mathlib/Topology/Connected/PathConnected.lean,Mathlib/Topology/Constructions.lean,Mathlib/Topology/ContinuousOn.lean,Mathlib/Topology/LocalAtTarget.lean,Mathlib/Topology/LocallyConstant/Basic.lean,Mathlib/Topology/Separation.lean,Mathlib/Topology/Sober.lean	18	3	['grunweg', 'rosborn']	nobody	563-4940 1 year ago	603-29497 1 year ago	0-0 0 seconds
12751	Command-Master author:Command-Master	feat: add lemmas for Nat/Bits, Nat/Bitwise and Nat/Size	Remove `@[simp]` from `Nat.bit_false` and `Nat.bit_true`, as `bit0` and `bit1` are deprecated, and add some lemmas to `Bits`, `Bitwise` and `Size`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor t-data	66/7	Mathlib/Data/Nat/Bits.lean,Mathlib/Data/Nat/Bitwise.lean,Mathlib/Data/Nat/Multiplicity.lean,Mathlib/Data/Nat/Size.lean	4	26	['Command-Master', 'Rida-Hamadani', 'Ruben-VandeVelde', 'YaelDillies', 'github-actions', 'jcommelin']	nobody	562-26094 1 year ago	567-42336 1 year ago	0-0 0 seconds
17127	FR-vdash-bot author:FR-vdash-bot	chore: remove global `Quotient.mk` `⟦·⟧` notation	--- Merge this PR when we are ready to migrate to `QuotLike` API (#16421). [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-data	137/2	Counterexamples/Pseudoelement.lean,Mathlib/Algebra/Associated/Basic.lean,Mathlib/Algebra/BigOperators/Group/Finset.lean,Mathlib/Algebra/Group/Conj.lean,Mathlib/Algebra/GroupWithZero/NonZeroDivisors.lean,Mathlib/Algebra/Order/CauSeq/Completion.lean,Mathlib/Algebra/Quandle.lean,Mathlib/AlgebraicGeometry/EllipticCurve/Jacobian.lean,Mathlib/AlgebraicGeometry/EllipticCurve/Projective.lean,Mathlib/AlgebraicTopology/FundamentalGroupoid/Basic.lean,Mathlib/AlgebraicTopology/FundamentalGroupoid/FundamentalGroup.lean,Mathlib/AlgebraicTopology/FundamentalGroupoid/InducedMaps.lean,Mathlib/AlgebraicTopology/FundamentalGroupoid/Product.lean,Mathlib/AlgebraicTopology/FundamentalGroupoid/SimplyConnected.lean,Mathlib/CategoryTheory/Abelian/Pseudoelements.lean,Mathlib/CategoryTheory/Limits/Shapes/SingleObj.lean,Mathlib/CategoryTheory/Monoidal/Free/Basic.lean,Mathlib/CategoryTheory/Monoidal/Free/Coherence.lean,Mathlib/CategoryTheory/Skeletal.lean,Mathlib/Data/Finset/Card.lean,Mathlib/Data/Fintype/List.lean,Mathlib/Data/Fintype/Quotient.lean,Mathlib/Data/Multiset/Basic.lean,Mathlib/Data/QPF/Multivariate/Constructions/Fix.lean,Mathlib/Data/QPF/Univariate/Basic.lean,Mathlib/Data/Quot.lean,Mathlib/Data/Real/Basic.lean,Mathlib/Data/Set/Finite.lean,Mathlib/Data/Set/Image.lean,Mathlib/Data/Setoid/Basic.lean,Mathlib/GroupTheory/GroupAction/Basic.lean,Mathlib/GroupTheory/GroupAction/Quotient.lean,Mathlib/LinearAlgebra/Dual.lean,Mathlib/LinearAlgebra/Ray.lean,Mathlib/Logic/Encodable/Basic.lean,Mathlib/Logic/Equiv/Basic.lean,Mathlib/ModelTheory/DirectLimit.lean,Mathlib/ModelTheory/Fraisse.lean,Mathlib/ModelTheory/Quotients.lean,Mathlib/NumberTheory/NumberField/CanonicalEmbedding/FundamentalCone.lean,Mathlib/NumberTheory/NumberField/Embeddings.lean,Mathlib/NumberTheory/NumberField/Units/DirichletTheorem.lean,Mathlib/NumberTheory/Padics/PadicIntegers.lean,Mathlib/NumberTheory/Padics/PadicNumbers.lean,Mathlib/Order/RelIso/Basic.lean,Mathlib/RepresentationTheory/Action/Concrete.lean,Mathlib/SetTheory/Cardinal/Basic.lean,Mathlib/SetTheory/Cardinal/Ordinal.lean,Mathlib/SetTheory/Game/Basic.lean,Mathlib/SetTheory/Game/Birthday.lean,Mathlib/SetTheory/Game/Impartial.lean,Mathlib/SetTheory/Game/Ordinal.lean,Mathlib/SetTheory/Game/State.lean,Mathlib/SetTheory/Lists.lean,Mathlib/SetTheory/Ordinal/Arithmetic.lean,Mathlib/SetTheory/Ordinal/Basic.lean,Mathlib/SetTheory/Surreal/Basic.lean,Mathlib/SetTheory/Surreal/Dyadic.lean,Mathlib/SetTheory/Surreal/Multiplication.lean,Mathlib/SetTheory/ZFC/Basic.lean,Mathlib/SetTheory/ZFC/Rank.lean,Mathlib/Topology/Connected/PathConnected.lean,Mathlib/Topology/Homotopy/HomotopyGroup.lean,Mathlib/Topology/Homotopy/Path.lean,Mathlib/Topology/Homotopy/Product.lean,Mathlib/Topology/MetricSpace/GromovHausdorff.lean,Mathlib/Topology/UniformSpace/Separation.lean,test/interactiveUnfold.lean	68	1	['github-actions']	nobody	520-63433 1 year ago	520-63433 1 year ago	0-0 0 seconds
14598	Command-Master author:Command-Master	chore: add typeclasses to unify various `add_top`, `add_eq_top`, etc.	Add the four typeclasses `IsTopAbsorbing`, `IsBotAbsorbing`, `NoTopSum`, `NoBotSum`, as additive equivalents for `MulZeroClass` and `NoZeroDivisors`. Add instances of these for `ENNReal`, `WithTop α`, `WithBot α`, `PUnit`, `EReal`, `PartENat`, `Measure`, `Interval` and `Filter`. Also split `Algebra/Order/AddGroupWithTop` to `Algebra/Order/Group/WithTop` and `Algebra/Order/Monoid/WithTop` --- Previous usages of lemmas with quantified names like `WithTop.add_top` have to be changed to just `add_top`. `add_lt_top` is `@[simp]`, in accordance with `ENNReal.add_lt_top` being `@[simp]`. This affects `WithTop.add_lt_top` which previously hadn't been `@[simp]`. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra t-order new-contributor label:t-algebra$	264/195	Archive/Wiedijk100Theorems/BallotProblem.lean,Mathlib.lean,Mathlib/Algebra/Order/Group/WithTop.lean,Mathlib/Algebra/Order/GroupWithZero/Canonical.lean,Mathlib/Algebra/Order/Interval/Basic.lean,Mathlib/Algebra/Order/Monoid/Unbundled/Basic.lean,Mathlib/Algebra/Order/Monoid/Unbundled/Defs.lean,Mathlib/Algebra/Order/Monoid/Unbundled/WithTop.lean,Mathlib/Algebra/Order/Monoid/WithTop.lean,Mathlib/Algebra/PUnitInstances/Order.lean,Mathlib/Algebra/Polynomial/Degree/Definitions.lean,Mathlib/Algebra/Polynomial/Monic.lean,Mathlib/Algebra/Tropical/Basic.lean,Mathlib/Analysis/Analytic/Meromorphic.lean,Mathlib/Analysis/Normed/Lp/ProdLp.lean,Mathlib/Analysis/NormedSpace/ENorm.lean,Mathlib/Analysis/SpecialFunctions/JapaneseBracket.lean,Mathlib/Analysis/SpecialFunctions/Log/ENNRealLog.lean,Mathlib/Data/ENNReal/Operations.lean,Mathlib/Data/ENat/Basic.lean,Mathlib/Data/Nat/PartENat.lean,Mathlib/Data/Nat/WithBot.lean,Mathlib/Data/Real/EReal.lean,Mathlib/LinearAlgebra/Lagrange.lean,Mathlib/MeasureTheory/Covering/Differentiation.lean,Mathlib/MeasureTheory/Decomposition/Lebesgue.lean,Mathlib/MeasureTheory/Function/ConditionalExpectation/CondexpL1.lean,Mathlib/MeasureTheory/Function/Jacobian.lean,Mathlib/MeasureTheory/Function/L1Space.lean,Mathlib/MeasureTheory/Function/L2Space.lean,Mathlib/MeasureTheory/Function/LpSeminorm/Basic.lean,Mathlib/MeasureTheory/Function/LpSeminorm/TriangleInequality.lean,Mathlib/MeasureTheory/Function/LpSpace.lean,Mathlib/MeasureTheory/Function/StronglyMeasurable/Basic.lean,Mathlib/MeasureTheory/Function/UniformIntegrable.lean,Mathlib/MeasureTheory/Integral/Bochner.lean,Mathlib/MeasureTheory/Integral/MeanInequalities.lean,Mathlib/MeasureTheory/Integral/SetIntegral.lean,Mathlib/MeasureTheory/Integral/VitaliCaratheodory.lean,Mathlib/MeasureTheory/Measure/Hausdorff.lean,Mathlib/MeasureTheory/Measure/Lebesgue/Basic.lean,Mathlib/MeasureTheory/Measure/LevyProkhorovMetric.lean,Mathlib/MeasureTheory/Measure/MeasureSpace.lean,Mathlib/MeasureTheory/Measure/MeasureSpaceDef.lean,Mathlib/MeasureTheory/Measure/Regular.lean,Mathlib/MeasureTheory/Measure/Typeclasses.lean,Mathlib/NumberTheory/Padics/PadicNumbers.lean,Mathlib/Order/Filter/Pointwise.lean,Mathlib/Probability/Kernel/Defs.lean,Mathlib/Probability/Martingale/Convergence.lean,Mathlib/RingTheory/Multiplicity.lean,Mathlib/RingTheory/MvPowerSeries/NoZeroDivisors.lean,Mathlib/RingTheory/UniqueFactorizationDomain.lean,Mathlib/Topology/EMetricSpace/Defs.lean,Mathlib/Topology/MetricSpace/Bounded.lean,Mathlib/Topology/MetricSpace/HausdorffDistance.lean,Mathlib/Topology/MetricSpace/Lipschitz.lean	57	30	['Command-Master', 'YaelDillies', 'github-actions']	nobody	483-58899 1 year ago	483-58899 1 year ago	0-0 0 seconds
19212	Julian author:Julian	feat(LinearAlgebra): add a variable_alias for VectorSpace	Taken directly from the variable_alias docs. Zulip: https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/why.20.5Bvariable_alias.5D.20attribute.20is.20not.20used.20in.20Mathlib.3F --- This is the first actual variable alias added to mathlib. I haven't reviewed variable_alias fully, but it seems like there's at least 3 ways they could be distributed in Mathlib: * alongside whatever subfolder they "belong to" (which is what I've tentatively done here) * In a file called `Aliases` somewhere near the thing they alias (which seems less discoverable to me) * In a single file, a la `Mathlib.TrainingWheels` (with some less playful name) which is meant to define a bunch of more "friendly" aliases all in one place. I kind of like the idea of the third thing as a future module but perhaps it can be synthesized if/when there are more aliases? For now as I say I've done the first one, but please let me know if someone prefers something else. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	25/0	Mathlib.lean,Mathlib/LinearAlgebra/VectorSpace.lean,scripts/noshake.json	3	10	['Julian', 'PieterCuijpers', 'github-actions', 'urkud']	nobody	463-35654 1 year ago	463-35654 1 year ago	0-0 0 seconds
19337	zeramorphic author:zeramorphic	feat(Data/Finsupp): generalise `Finsupp` to any "zero" value	Remove the explicit dependence of `Finsupp` on `[Zero M]`, instead defining `Finsupp'` (better name pending) to be functions that are equal to a fixed value `z : M` cofinitely often. This PR is intended to do the initial work of replacing the definition of `Finsupp` with an instantiation of the more general definition, without adding any appropriate API. If accepted, the API development will follow in later PRs. Issues to consider: - Naming of `Finsupp'.` - Where should `Finsupp'` lemmas go? Do they need their own file/folder under `Data/`? Relevant Zulip threads: - https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/Finsupp.20generalisations - https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/Finsupp-like.20partial.20function Comments are welcome. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-data	203/83	Archive/Wiedijk100Theorems/Partition.lean,Mathlib/Algebra/MvPolynomial/Basic.lean,Mathlib/Algebra/MvPolynomial/Rename.lean,Mathlib/Algebra/MvPolynomial/Variables.lean,Mathlib/Algebra/Polynomial/Basic.lean,Mathlib/Algebra/Polynomial/Laurent.lean,Mathlib/Data/Finsupp/BigOperators.lean,Mathlib/Data/Finsupp/Defs.lean,Mathlib/Data/Finsupp/Order.lean,Mathlib/Data/Nat/Choose/Multinomial.lean,Mathlib/RingTheory/MvPolynomial/Symmetric/Defs.lean,Mathlib/RingTheory/PowerBasis.lean,scripts/nolints_prime_decls.txt	13	5	['github-actions', 'vihdzp', 'zeramorphic']	nobody	461-11731 1 year ago	461-11731 1 year ago	0-0 0 seconds
18756	astrainfinita author:astrainfinita	refactor: deprecate `DistribMulActionSemiHomClass` `MulSemiringActionSemiHomClass`	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	50/28	Mathlib/Algebra/Algebra/NonUnitalHom.lean,Mathlib/Algebra/Module/LinearMap/Defs.lean,Mathlib/GroupTheory/GroupAction/Hom.lean	3	4	['astrainfinita', 'github-actions', 'leanprover-bot']	nobody	449-63800 1 year ago	449-63800 1 year ago	0-0 0 seconds
20527	trivial1711 author:trivial1711	refactor(Topology/UniformSpace/Completion): more descriptive names for `α → Completion α`	- We rename the various maps `α → Completion α` in order to make their names more consistent. - Let `α` be a uniform space. We rename the uniformly continuous function `α → Completion α` from `UniformSpace.Completion.coe'` to `UniformSpace.Completion.coe`. - Let `α` be a uniform additive group. We rename the additive group homomorphism `α →+ Completion α` from `UniformSpace.Completion.toCompl` to `UniformSpace.Completion.coeAddHom`. - Let `α` be a uniform ring. The ring homomorphism `α →+* Completion α` is called `UniformSpace.Completion.coeRingHom`; its name is unchanged. - Let `α` be a normed space over a field `𝕜`. We rename the linear isometry `α →ₗᵢ[𝕜] Completion α` from `UniformSpace.Completion.toComplₗᵢ` to `UniformSpace.Completion.coeₗᵢ`. - Let `α` be a normed space over a field `𝕜`. We rename the continuous linear map `α →L[𝕜] Completion α` from `UniformSpace.Completion.toComplL` to `UniformSpace.Completion.coeL`. - Let `α` be a normed additive group. We rename the norm preserving homomorphism `NormedAddGroupHom α (Completion α)` from `NormedAddCommGroup.toCompl` to `UniformSpace.Completion.coeNormedAddGroupHom`. - We analogously rename some other theorems. - We add some trivial theorems (all of which are proved by `rfl`) that state that the functions considered above are equal. We give all of them the `simp` and `norm_cast` attributes. - We add a new theorem `UniformSpace.Completion.coeAddHom_eq_coe` that states that `UniformSpace.Completion.coeAddHom` and `UniformSpace.Completion.coe` are equal as functions. - We similarly add a new theorem `UniformSpace.Completion.coeRingHom_eq_coe`. - We rename the theorem `UniformSpace.Completion.coe_toComplₗᵢ` to `UniformSpace.Completion.coeₗᵢ_eq_coe`. - We rename the theorem `UniformSpace.Completion.coe_toComplL` to `UniformSpace.Completion.coeL_eq_coe`. - We similarly add a new theorem `UniformSpace.Completion.coeNormedAddGroupHom_eq_coe`. - We change all occurrences of the string `((↑) : α → Completion α)` to `(coe : α → Completion α)` or just `coe`. - We put the statements of some theorems into simp normal form by using the plain function `coe` rather than the homomorphisms that carry more structure. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology	130/92	Mathlib/Analysis/Analytic/Uniqueness.lean,Mathlib/Analysis/Calculus/FDeriv/Analytic.lean,Mathlib/Analysis/Complex/AbsMax.lean,Mathlib/Analysis/Complex/Liouville.lean,Mathlib/Analysis/InnerProductSpace/Completion.lean,Mathlib/Analysis/Normed/Group/HomCompletion.lean,Mathlib/Analysis/Normed/Module/Completion.lean,Mathlib/Analysis/SpecialFunctions/NonIntegrable.lean,Mathlib/MeasureTheory/Integral/IntegralEqImproper.lean,Mathlib/Topology/Algebra/GroupCompletion.lean,Mathlib/Topology/Algebra/InfiniteSum/GroupCompletion.lean,Mathlib/Topology/Algebra/InfiniteSum/Nonarchimedean.lean,Mathlib/Topology/Algebra/Nonarchimedean/Completion.lean,Mathlib/Topology/Algebra/UniformRing.lean,Mathlib/Topology/Category/UniformSpace.lean,Mathlib/Topology/MetricSpace/Completion.lean,Mathlib/Topology/UniformSpace/Completion.lean	17	4	['eric-wieser', 'github-actions', 'trivial1711']	nobody	415-24606 1 year ago	415-24606 1 year ago	0-0 0 seconds
18474	FR-vdash-bot author:FR-vdash-bot	perf: lower the priority of `WithOne.to` instances	--- From #7873. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra slow-typeclass-synthesis t-data label:t-algebra$	9/2	Mathlib/Algebra/Polynomial/BigOperators.lean,Mathlib/Data/Int/Cast/Defs.lean,Mathlib/Data/Nat/Cast/Defs.lean	3	7	['FR-vdash-bot', 'eric-wieser', 'github-actions', 'leanprover-bot']	nobody	413-11636 1 year ago	413-11636 1 year ago	0-0 0 seconds
20372	jvlmdr author:jvlmdr	feat(MeasureTheory/Function): Add ContinuousLinearMap.bilinearCompLp(L)	Introduce ContinuousLinearMap.bilinearCompLp and bilinearCompLpL. Generalize eLpNorm_le_eLpNorm_mul_eLpNorm theorems to include constant C in bound condition. --- Expect this may be useful for defining tempered distributions from functions in `L^p`. The definitions more or less follow `ContinuousLinearMap.compLp...`. Names are loosely analogous to `ContinuousLinearMap.bilinearComp` and `SchwartzMap.bilinLeftCLM`. Note: I preferred the spelling `hpqr : p⁻¹ + q⁻¹ = r⁻¹` with `f` in `L^p` and `g` in `L^q` to `hpqr : 1 / p = 1 / q + 1 / r`. It's easier to obtain from `ENNReal.IsConjExponent` too. A few questions: - [ ] I defined `bilinear{Left,Right}LpL` in addition to `bilinearCompLpL` because `LinearMap.mkContinuous₂` is marked as `noncomputable` and `LinearMap.mkContinuous` is not. Is this worth the extra definitions? (Note: This is not visible in the source due to `noncomputable section`.) - [ ] Should I use `C : ℝ` instead of `C : NNReal` for `eLpNorm_le_eLpNorm_mul_eLpNorm'_of_norm'`? - [ ] Is it going to be painful to have `[Fact (1 ≤ p)] [Fact (1 ≤ q)] [Fact (1 ≤ r)]`? I don't think there's a way to avoid it though. Maybe providing specialized versions for `p.IsConjExponent q` with `L^1`? Naming: - [ ] Is it satisfactory to add a `'` to the `eLpNorm_le_eLpNorm_mul_eLpNorm ` definitions in `CompareExp.lean` where `≤ ‖f x‖ * ‖g x‖` has been replaced with `≤ C * ‖f x‖ * ‖g x‖`? These could replace the existing theorems, although I don't want to break backwards compatibility. There are 5 instances: `eLpNorm_le_eLpNorm_top_mul_eLpNorm'`, `eLpNorm_le_eLpNorm_mul_eLpNorm_top'`, `eLpNorm'_le_eLpNorm'_mul_eLpNorm''`, `eLpNorm_le_eLpNorm_mul_eLpNorm_of_nnnorm'`, `eLpNorm_le_eLpNorm_mul_eLpNorm'_of_norm'` (I'm not sure why the existing theorem `eLpNorm_le_eLpNorm_mul_eLpNorm'_of_norm` has an internal `'`) - [ ] Is `bilinearLeftLpL` a suitable name? Other options: `bilinearCompLpLeftL`, `bilinearCompLeftLpL`, `bilinLeftLpL` (analogous to `SchwartzMap.bilinLeftCLM`) [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-measure-probability new-contributor	203/40	Mathlib/MeasureTheory/Function/LpSeminorm/CompareExp.lean,Mathlib/MeasureTheory/Function/LpSpace.lean	2	1	['github-actions']	nobody	400-35893 1 year ago	400-35893 1 year ago	0-0 0 seconds
21959	BGuillemet author:BGuillemet	feat(Topology/ContinuousMap): Stone-Weierstrass theorem for MvPolynomial	Add the subalgebra of multivariate polynomials and prove it separates points, on the same model as `ContinuousMap/Polynomial.lean`. Prove the Stone-Weierstrass theorem and some variations for multivariate polynomials. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology new-contributor	285/1	Mathlib.lean,Mathlib/Topology/ContinuousMap/MvPolynomial.lean,Mathlib/Topology/ContinuousMap/StoneWeierstrass.lean	3	1	['github-actions']	nobody	364-21914 11 months ago	364-21914 11 months ago	0-0 0 seconds
22660	Ruben-VandeVelde author:Ruben-VandeVelde	chore: follow naming convention around Group.IsNilpotent	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	133/67	Mathlib/GroupTheory/Frattini.lean,Mathlib/GroupTheory/Nilpotent.lean,Mathlib/GroupTheory/SpecificGroups/ZGroup.lean	3	1	['github-actions']	nobody	352-44169 11 months ago	352-44169 11 months ago	0-0 0 seconds
21488	imbrem author:imbrem	feat(CategoryTheory/Monoidal): premonoidal categories	Add support for premonoidal categories --- Still want to add support for: - Premonoidal braided/symmetric categories - The monoidal coherence theorem, which I've already ported in my `discretion` library - The `coherence` tactic, which should work fine for premonoidal categories too but wanted to get this in front of reviewers ASAP to make sure my general approach was alright [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-category-theory new-contributor	900/361	Mathlib/Algebra/Category/ModuleCat/Presheaf/Monoidal.lean,Mathlib/CategoryTheory/Bicategory/End.lean,Mathlib/CategoryTheory/GradedObject/Monoidal.lean,Mathlib/CategoryTheory/Localization/Monoidal.lean,Mathlib/CategoryTheory/Monoidal/Braided/Basic.lean,Mathlib/CategoryTheory/Monoidal/Category.lean,Mathlib/CategoryTheory/Monoidal/Center.lean,Mathlib/CategoryTheory/Monoidal/CoherenceLemmas.lean,Mathlib/CategoryTheory/Monoidal/Discrete.lean,Mathlib/CategoryTheory/Monoidal/End.lean,Mathlib/CategoryTheory/Monoidal/Free/Basic.lean,Mathlib/CategoryTheory/Monoidal/Functor.lean,Mathlib/CategoryTheory/Monoidal/FunctorCategory.lean,Mathlib/CategoryTheory/Monoidal/Mon_.lean,Mathlib/CategoryTheory/Monoidal/Opposite.lean,Mathlib/CategoryTheory/Monoidal/Transport.lean,Mathlib/Tactic/CategoryTheory/Monoidal/Datatypes.lean,Mathlib/Tactic/CategoryTheory/Monoidal/Normalize.lean,Mathlib/Tactic/CategoryTheory/Monoidal/PureCoherence.lean,Mathlib/Tactic/CategoryTheory/MonoidalComp.lean,MathlibTest/StringDiagram.lean	21	9	['YaelDillies', 'github-actions', 'grunweg', 'imbrem', 'kim-em', 'leanprover-community-bot-assistant']	nobody	329-30316 10 months ago	329-30317 10 months ago	0-0 0 seconds
21525	sinhp author:sinhp	feat(CategoryTheory): Locally Cartesian Closed Categories (Prelim)	This PR defines the basic preliminaries for defining locally cartesian closed categories (LCCCs). In particular, using the calculus of mates we define certain natural isomorphisms involving `Over.star` and `Over.pullback` which will be crucial in defining the right adjoint to the pullback functor in the development of LCCCs. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-category-theory large-import	338/24	Mathlib/CategoryTheory/Comma/Over/Basic.lean,Mathlib/CategoryTheory/Comma/Over/Pullback.lean,Mathlib/CategoryTheory/Galois/Examples.lean	3	13	['b-mehta', 'github-actions', 'joelriou', 'leanprover-community-bot-assistant', 'sinhp']	nobody	329-30314 10 months ago	329-30316 10 months ago	0-0 0 seconds
16314	FR-vdash-bot author:FR-vdash-bot	chore(Data/Quot): deprecate `ind*'` APIs	--- - [x] depends on: #16264 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-data	247/287	Counterexamples/CliffordAlgebraNotInjective.lean,Mathlib/Algebra/Colimit/Module.lean,Mathlib/Algebra/Lie/Quotient.lean,Mathlib/Algebra/Module/Torsion.lean,Mathlib/Algebra/RingQuot.lean,Mathlib/Analysis/SpecialFunctions/Trigonometric/Angle.lean,Mathlib/CategoryTheory/ConnectedComponents.lean,Mathlib/CategoryTheory/Subobject/Basic.lean,Mathlib/CategoryTheory/Subobject/FactorThru.lean,Mathlib/CategoryTheory/Subobject/Lattice.lean,Mathlib/Computability/Reduce.lean,Mathlib/Computability/Tape.lean,Mathlib/Data/List/Cycle.lean,Mathlib/Data/Multiset/MapFold.lean,Mathlib/Data/Multiset/ZeroCons.lean,Mathlib/Data/Quot.lean,Mathlib/Data/Setoid/Basic.lean,Mathlib/Data/Setoid/Partition.lean,Mathlib/FieldTheory/Fixed.lean,Mathlib/GroupTheory/Complement.lean,Mathlib/GroupTheory/Congruence/Basic.lean,Mathlib/GroupTheory/Congruence/Defs.lean,Mathlib/GroupTheory/Congruence/Hom.lean,Mathlib/GroupTheory/Coset/Basic.lean,Mathlib/GroupTheory/Coset/Defs.lean,Mathlib/GroupTheory/FreeAbelianGroup.lean,Mathlib/GroupTheory/GroupAction/Basic.lean,Mathlib/GroupTheory/GroupAction/Defs.lean,Mathlib/GroupTheory/GroupAction/Quotient.lean,Mathlib/GroupTheory/Index.lean,Mathlib/GroupTheory/MonoidLocalization/Basic.lean,Mathlib/GroupTheory/PGroup.lean,Mathlib/GroupTheory/Perm/Cycle/Concrete.lean,Mathlib/GroupTheory/PresentedGroup.lean,Mathlib/GroupTheory/QuotientGroup/Basic.lean,Mathlib/GroupTheory/QuotientGroup/Defs.lean,Mathlib/GroupTheory/SchurZassenhaus.lean,Mathlib/GroupTheory/Sylow.lean,Mathlib/LinearAlgebra/Alternating/DomCoprod.lean,Mathlib/LinearAlgebra/Projectivization/Basic.lean,Mathlib/LinearAlgebra/Quotient/Basic.lean,Mathlib/LinearAlgebra/Quotient/Defs.lean,Mathlib/MeasureTheory/Function/AEEqFun.lean,Mathlib/NumberTheory/Padics/PadicNumbers.lean,Mathlib/NumberTheory/RamificationInertia/Basic.lean,Mathlib/Order/Antisymmetrization.lean,Mathlib/Order/Category/PartOrd.lean,Mathlib/Order/Filter/Germ/Basic.lean,Mathlib/RepresentationTheory/GroupCohomology/Hilbert90.lean,Mathlib/RingTheory/AdicCompletion/Algebra.lean,Mathlib/RingTheory/AdicCompletion/Basic.lean,Mathlib/RingTheory/AdicCompletion/Functoriality.lean,Mathlib/RingTheory/AdjoinRoot.lean,Mathlib/RingTheory/Congruence/Basic.lean,Mathlib/RingTheory/Flat/FaithfullyFlat/Basic.lean,Mathlib/RingTheory/GradedAlgebra/HomogeneousLocalization.lean,Mathlib/RingTheory/Ideal/Cotangent.lean,Mathlib/RingTheory/Ideal/Norm/AbsNorm.lean,Mathlib/RingTheory/Ideal/Quotient/Basic.lean,Mathlib/RingTheory/Ideal/Quotient/Defs.lean,Mathlib/RingTheory/Ideal/Quotient/Operations.lean,Mathlib/RingTheory/Valuation/Quotient.lean,Mathlib/Topology/Algebra/Group/TopologicalAbelianization.lean,Mathlib/Topology/Algebra/InfiniteSum/Module.lean,Mathlib/Topology/Separation/Basic.lean	65	4	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot']	nobody	323-55280 10 months ago	323-55282 10 months ago	0-0 0 seconds
15483	FR-vdash-bot author:FR-vdash-bot	chore(GroupTheory/Coset): reduce defeq abuse	--- - [x] depends on: #15482 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	114/60	Mathlib/GroupTheory/Commensurable.lean,Mathlib/GroupTheory/Coset.lean,Mathlib/GroupTheory/QuotientGroup.lean,Mathlib/LinearAlgebra/Alternating/DomCoprod.lean,Mathlib/MeasureTheory/Measure/Haar/Quotient.lean,Mathlib/Topology/Algebra/Group/Compact.lean	6	14	['FR-vdash-bot', 'eric-wieser', 'github-actions', 'grunweg', 'leanprover-bot', 'leanprover-community-mathlib4-bot', 'mattrobball', 'mergify', 'urkud']	nobody	323-173 10 months ago	571-38503 1 year ago	0-0 0 seconds
23859	urkud author:urkud	feat(Topology/../Order/Field): generalize to `Semifield`	.. from a linear ordered field to a linear ordered semifield--- - [ ] depends on: #23857 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology	245/219	Mathlib/Algebra/Order/Group/Pointwise/Interval.lean,Mathlib/Analysis/BoxIntegral/Box/SubboxInduction.lean,Mathlib/Topology/Algebra/Order/Field.lean,Mathlib/Topology/Order/Basic.lean	4	3	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot']	nobody	316-43190 10 months ago	316-43193 10 months ago	0-0 0 seconds
23810	b-reinke author:b-reinke	chore(Order/Interval): generalize succ/pred lemmas to partial orders	Many lemmas in `Mathlib/Order/Interval/Set/SuccPred.lean`and `Mathlib/Order/Interval/Finset/SuccPred.lean` also work for partial orders. They are generalized in this PR by introducing different sections for `PartialOrder` and `LinearOrder` assumptions in the respective files. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-order	231/89	Mathlib/Order/Interval/Finset/SuccPred.lean,Mathlib/Order/Interval/Set/SuccPred.lean	2	2	['github-actions', 'leanprover-community-bot-assistant']	nobody	314-19965 10 months ago	314-19967 10 months ago	0-0 0 seconds
24285	madvorak author:madvorak	chore(Algebra/*-{Category,Homology}): remove unnecessary universe variables	Discussions: https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Call.20for.20help.3A.20technical.2F.20organisational.20debt/with/513620128 https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Algebra.20and.20.60Type.60/with/513558902 https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Task.2026.3A.20Replace.20Type.20u.20by.20Type.20wherever.20possible/with/513592993 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	542/916	Mathlib/Algebra/AddTorsor/Basic.lean,Mathlib/Algebra/Algebra/Defs.lean,Mathlib/Algebra/Algebra/Equiv.lean,Mathlib/Algebra/Algebra/Field.lean,Mathlib/Algebra/Algebra/Hom.lean,Mathlib/Algebra/Algebra/Operations.lean,Mathlib/Algebra/Algebra/Spectrum/Basic.lean,Mathlib/Algebra/Algebra/Subalgebra/Lattice.lean,Mathlib/Algebra/Algebra/Subalgebra/Tower.lean,Mathlib/Algebra/Algebra/Tower.lean,Mathlib/Algebra/Central/Basic.lean,Mathlib/Algebra/Central/Defs.lean,Mathlib/Algebra/Central/TensorProduct.lean,Mathlib/Algebra/CharP/Pi.lean,Mathlib/Algebra/CharP/Quotient.lean,Mathlib/Algebra/CharP/Subring.lean,Mathlib/Algebra/DirectSum/Algebra.lean,Mathlib/Algebra/DirectSum/Basic.lean,Mathlib/Algebra/DirectSum/Finsupp.lean,Mathlib/Algebra/DirectSum/Module.lean,Mathlib/Algebra/EuclideanDomain/Basic.lean,Mathlib/Algebra/EuclideanDomain/Defs.lean,Mathlib/Algebra/Field/Basic.lean,Mathlib/Algebra/Field/Defs.lean,Mathlib/Algebra/Field/IsField.lean,Mathlib/Algebra/Field/MinimalAxioms.lean,Mathlib/Algebra/Field/Subfield/Basic.lean,Mathlib/Algebra/Field/Subfield/Defs.lean,Mathlib/Algebra/FreeNonUnitalNonAssocAlgebra.lean,Mathlib/Algebra/Group/Conj.lean,Mathlib/Algebra/Group/Defs.lean,Mathlib/Algebra/Group/Equiv/Finite.lean,Mathlib/Algebra/Group/Ext.lean,Mathlib/Algebra/Group/Hom/End.lean,Mathlib/Algebra/Group/Hom/Instances.lean,Mathlib/Algebra/Group/Invertible/Basic.lean,Mathlib/Algebra/Group/Invertible/Defs.lean,Mathlib/Algebra/Group/Pi/Basic.lean,Mathlib/Algebra/Group/Pi/Lemmas.lean,Mathlib/Algebra/Group/TypeTags/Basic.lean,Mathlib/Algebra/Group/TypeTags/Finite.lean,Mathlib/Algebra/Group/TypeTags/Hom.lean,Mathlib/Algebra/Group/Units/Basic.lean,Mathlib/Algebra/Group/Units/Defs.lean,Mathlib/Algebra/Group/Units/Hom.lean,Mathlib/Algebra/Group/WithOne/Basic.lean,Mathlib/Algebra/Group/WithOne/Defs.lean,Mathlib/Algebra/GroupWithZero/Action/Pi.lean,Mathlib/Algebra/GroupWithZero/Defs.lean,Mathlib/Algebra/GroupWithZero/Invertible.lean,Mathlib/Algebra/GroupWithZero/NeZero.lean,Mathlib/Algebra/Lie/Abelian.lean,Mathlib/Algebra/Lie/Basic.lean,Mathlib/Algebra/Lie/CartanMatrix.lean,Mathlib/Algebra/Lie/CartanSubalgebra.lean,Mathlib/Algebra/Lie/Character.lean,Mathlib/Algebra/Lie/Classical.lean,Mathlib/Algebra/Lie/DirectSum.lean,Mathlib/Algebra/Lie/Free.lean,Mathlib/Algebra/Lie/Ideal.lean,Mathlib/Algebra/Lie/IdealOperations.lean,Mathlib/Algebra/Lie/Matrix.lean,Mathlib/Algebra/Lie/Nilpotent.lean,Mathlib/Algebra/Lie/NonUnitalNonAssocAlgebra.lean,Mathlib/Algebra/Lie/OfAssociative.lean,Mathlib/Algebra/Lie/Quotient.lean,Mathlib/Algebra/Lie/SkewAdjoint.lean,Mathlib/Algebra/Lie/Solvable.lean,Mathlib/Algebra/Lie/Subalgebra.lean,Mathlib/Algebra/Lie/Submodule.lean,Mathlib/Algebra/Lie/TensorProduct.lean,Mathlib/Algebra/Lie/UniversalEnveloping.lean,Mathlib/Algebra/Module/Basic.lean,Mathlib/Algebra/Module/CharacterModule.lean,Mathlib/Algebra/Module/DedekindDomain.lean,Mathlib/Algebra/Module/Defs.lean,Mathlib/Algebra/Module/End.lean,Mathlib/Algebra/Module/Equiv/Opposite.lean,Mathlib/Algebra/Module/Lattice.lean,Mathlib/Algebra/Module/LinearMap/Basic.lean,Mathlib/Algebra/Module/LinearMap/Defs.lean,Mathlib/Algebra/Module/LinearMap/End.lean,Mathlib/Algebra/Module/LocalizedModule/Basic.lean,Mathlib/Algebra/Module/MinimalAxioms.lean,Mathlib/Algebra/Module/NatInt.lean,Mathlib/Algebra/Module/Opposite.lean,Mathlib/Algebra/Module/Pi.lean,Mathlib/Algebra/Module/Presentation/Differentials.lean,Mathlib/Algebra/Module/Presentation/Tensor.lean,Mathlib/Algebra/Module/Rat.lean,Mathlib/Algebra/Module/RingHom.lean,Mathlib/Algebra/Module/Submodule/Basic.lean,Mathlib/Algebra/Module/Torsion.lean,Mathlib/Algebra/MonoidAlgebra/Basic.lean,Mathlib/Algebra/MonoidAlgebra/Defs.lean,Mathlib/Algebra/MonoidAlgebra/Support.lean,Mathlib/Algebra/MvPolynomial/Basic.lean,Mathlib/Algebra/MvPolynomial/CommRing.lean,Mathlib/Algebra/MvPolynomial/Degrees.lean,Mathlib/Algebra/MvPolynomial/Equiv.lean	182	22	['erdOne', 'github-actions', 'leanprover-bot', 'leanprover-community-bot-assistant', 'madvorak', 'mattrobball']	nobody	314-8662 10 months ago	314-8663 10 months ago	0-0 0 seconds
13649	FR-vdash-bot author:FR-vdash-bot	chore: redefine `Nat.div2` `Nat.bodd`	The new definitions are faster than the old ones. `Nat.binaryRec` will be moved to batteries (https://github.com/leanprover-community/batteries/pull/799) or core (https://github.com/leanprover/lean4/pull/3756), so relevant contents are moved to a new file temporarily. --- - [x] depends on: #15567 - [x] depends on: #19666 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict	63/88	Mathlib/Computability/Primrec.lean,Mathlib/Data/Int/Bitwise.lean,Mathlib/Data/Nat/Bits.lean,Mathlib/Data/Nat/Bitwise.lean,Mathlib/Data/Nat/Size.lean,Mathlib/Logic/Denumerable.lean,Mathlib/Logic/Encodable/Basic.lean,Mathlib/Logic/Equiv/Nat.lean	8	15	['FR-vdash-bot', 'digama0', 'eric-wieser', 'github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot', 'urkud']	digama0 assignee:digama0	305-78612 10 months ago	305-78614 10 months ago	0-0 0 seconds
23546	JovanGerb author:JovanGerb	feat(LinearAlgebra/AffineSpace/AffineSubspace): rename `AffineSubspace.mk'` to `Submodule.shift`	In addition to renaming, I've refactored the code a bit: - `mem_mk'_iff_vsub_mem` was obsolete since it was the same as `mem_mk'`, so I removed it (this is due to a change in the definition I made recently) - I added a nonempty instance for `shift` - I added a simp lemma that `shift` isn't equal to `⊥` (the empty affine subspace). I need this for the next point. - Edit: I'll leave this for a later PR. ~I proved a simp lemma that a `shift` is parallel to a `shift` if and only if the linear subspaces are the same.~ - I renamed `mk'_eq` to `shift_direction_eq_self `. - I renamed `eq_or_eq_secondInter_of_mem_mk'_span_singleton_iff_mem` to `eq_or_eq_secondInter_iff_mem_of_mem_shift_span_singleton`. I think it is better to put the `of_mem_mk'_span_singleton` at the end of the name. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-euclidean-geometry	128/99	Mathlib/Algebra/Module/ZLattice/Basic.lean,Mathlib/Geometry/Euclidean/Basic.lean,Mathlib/Geometry/Euclidean/MongePoint.lean,Mathlib/Geometry/Euclidean/PerpBisector.lean,Mathlib/Geometry/Euclidean/Sphere/SecondInter.lean,Mathlib/Geometry/Euclidean/Sphere/Tangent.lean,Mathlib/LinearAlgebra/AffineSpace/AffineSubspace/Defs.lean	7	4	['JovanGerb', 'github-actions', 'leanprover-community-bot-assistant']	nobody	304-25194 10 months ago	304-25195 10 months ago	0-0 0 seconds
23349	BGuillemet author:BGuillemet	feat: add LocallyLipschitzOn.lipschitzOnWith_of_isCompact and two small lemmas about Lipschitz functions	Main feat (in Mathlib/Topology/EMetricSpace/Basic.lean): if a function `f` from an extended pseudometric space to a pseudometric space is locally Lipschitz on a compact subset `s`, then `f` is Lipschitz on `s`. The theorem is true only when the codomain of `f` is a pseudometric space, so it needs imports from Mathlib/Topology/MetricSpace. Other small feat (in Mathlib/Analysis/Calculus/ContDiff/RCLike.lean): a function that is continuously differentiable on an open subset is locally Lipschitz on this subset. --- - [ ] depends on: #22890 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology new-contributor large-import	59/4	Mathlib/Analysis/Calculus/ContDiff/RCLike.lean,Mathlib/Topology/EMetricSpace/Lipschitz.lean	2	4	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot']	PatrickMassot assignee:PatrickMassot	281-15412 9 months ago	281-15414 9 months ago	0-0 0 seconds
25340	dupuisf author:dupuisf	chore(Analysis/Convex): move files pertaining to convex/concave functions to their own folder	This PR creates a new folder under `Analysis/Convex` called `Analysis/Convex/Function`, which includes files that are mostly or entirely about convex/concave functions (as opposed to convex sets). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-convex-geometry	4264/4155	Mathlib.lean,Mathlib/Analysis/Convex/Continuous.lean,Mathlib/Analysis/Convex/Deriv.lean,Mathlib/Analysis/Convex/Exposed.lean,Mathlib/Analysis/Convex/Extrema.lean,Mathlib/Analysis/Convex/Function.lean,Mathlib/Analysis/Convex/Function/Basic.lean,Mathlib/Analysis/Convex/Function/Continuous.lean,Mathlib/Analysis/Convex/Function/Deriv.lean,Mathlib/Analysis/Convex/Function/Extrema.lean,Mathlib/Analysis/Convex/Function/Integral.lean,Mathlib/Analysis/Convex/Function/Jensen.lean,Mathlib/Analysis/Convex/Function/Mul.lean,Mathlib/Analysis/Convex/Function/Piecewise.lean,Mathlib/Analysis/Convex/Function/Quasiconvex.lean,Mathlib/Analysis/Convex/Function/Slope.lean,Mathlib/Analysis/Convex/Function/Strong.lean,Mathlib/Analysis/Convex/Integral.lean,Mathlib/Analysis/Convex/Jensen.lean,Mathlib/Analysis/Convex/Mul.lean,Mathlib/Analysis/Convex/Piecewise.lean,Mathlib/Analysis/Convex/Quasiconvex.lean,Mathlib/Analysis/Convex/Slope.lean,Mathlib/Analysis/Convex/SpecificFunctions/Basic.lean,Mathlib/Analysis/Convex/SpecificFunctions/Deriv.lean,Mathlib/Analysis/Convex/Strong.lean,Mathlib/Analysis/MeanInequalities.lean,Mathlib/Analysis/MeanInequalitiesPow.lean,Mathlib/Analysis/Normed/Module/Convex.lean,Mathlib/Analysis/Seminorm.lean,Mathlib/Analysis/SpecialFunctions/Log/NegMulLog.lean,Mathlib/Analysis/SpecialFunctions/Pochhammer.lean,Mathlib/MeasureTheory/Measure/Decomposition/IntegralRNDeriv.lean,Mathlib/NumberTheory/Harmonic/GammaDeriv.lean	34	2	['github-actions', 'leanprover-community-bot-assistant']	nobody	270-38239 8 months ago	270-38241 8 months ago	0-0 0 seconds
18441	ADedecker author:ADedecker	refactor(AdicTopology): use new API for algebraic filter bases, and factor some code	--- - [x] depends on: #18437 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology t-algebra label:t-algebra$	847/159	Mathlib.lean,Mathlib/Topology/Algebra/FilterBasis.lean,Mathlib/Topology/Algebra/FilterBasisNew.lean,Mathlib/Topology/Algebra/Nonarchimedean/AdicTopology.lean,Mathlib/Topology/Algebra/Nonarchimedean/Bases.lean,Mathlib/Topology/Algebra/Nonarchimedean/BasesNew.lean	6	3	['ADedecker', 'github-actions', 'mathlib4-dependent-issues-bot']	nobody	258-29980 8 months ago	258-29982 8 months ago	0-0 0 seconds
18439	ADedecker author:ADedecker	refactor: use new algebraic filter bases API in `FiniteAdeleRing`	--- - [x] depends on: #18437 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology t-algebra label:t-algebra$	699/21	Mathlib.lean,Mathlib/RingTheory/DedekindDomain/FiniteAdeleRing.lean,Mathlib/Topology/Algebra/FilterBasis.lean,Mathlib/Topology/Algebra/FilterBasisNew.lean,Mathlib/Topology/Algebra/Nonarchimedean/Bases.lean,Mathlib/Topology/Algebra/Nonarchimedean/BasesNew.lean	6	2	['github-actions', 'mathlib4-dependent-issues-bot']	nobody	258-29978 8 months ago	258-29980 8 months ago	0-0 0 seconds
18438	ADedecker author:ADedecker	refactor: adapt `KrullTopology` to the new algebraic filter bases API	--- - [x] depends on: #18437 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology t-algebra label:t-algebra$	771/168	Mathlib.lean,Mathlib/FieldTheory/KrullTopology.lean,Mathlib/Topology/Algebra/FilterBasis.lean,Mathlib/Topology/Algebra/FilterBasisNew.lean,Mathlib/Topology/Algebra/Nonarchimedean/Bases.lean,Mathlib/Topology/Algebra/Nonarchimedean/BasesNew.lean	6	5	['ADedecker', 'AntoineChambert-Loir', 'github-actions', 'mathlib4-dependent-issues-bot']	nobody	258-29977 8 months ago	258-29978 8 months ago	0-0 0 seconds
13964	pechersky author:pechersky	feat(Data/DigitExpansion): begin defining variant of reals without rationals	Based on a de Bruijn 1976 paper. This file is just the basic definition of a digit expansion. Will be followed up with further constructions. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-data	518/0	Mathlib.lean,Mathlib/Data/DigitExpansion/Defs.lean,docs/references.bib	3	11	['eric-wieser', 'github-actions', 'kim-em', 'pechersky']	dupuisf assignee:dupuisf	255-12268 8 months ago	493-38484 1 year ago	0-0 0 seconds
24823	eric-wieser author:eric-wieser	refactor: add `hom` lemmas for the `MonoidalCategory` structure on `ModuleCat`	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	148/164	Mathlib/Algebra/Category/FGModuleCat/Basic.lean,Mathlib/Algebra/Category/ModuleCat/Adjunctions.lean,Mathlib/Algebra/Category/ModuleCat/Monoidal/Basic.lean,Mathlib/Algebra/Category/ModuleCat/Monoidal/Closed.lean,Mathlib/Algebra/Category/ModuleCat/Monoidal/Symmetric.lean,Mathlib/Algebra/Category/ModuleCat/Presheaf/Free.lean,Mathlib/Algebra/Category/ModuleCat/Presheaf/Generator.lean,Mathlib/Algebra/Category/ModuleCat/Presheaf/Monoidal.lean,Mathlib/CategoryTheory/Monoidal/Internal/Module.lean,Mathlib/RepresentationTheory/Coinvariants.lean,Mathlib/RepresentationTheory/Rep.lean	11	21	['101damnations', 'YaelDillies', 'eric-wieser', 'github-actions', 'joelriou', 'kbuzzard', 'leanprover-community-bot-assistant']	101damnations assignee:101damnations	242-63328 7 months ago	242-63328 7 months ago	0-0 0 seconds
25071	erdOne author:erdOne	feat(EllipticCurve): basic API for singular cubics	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebraic-geometry	320/0	Mathlib.lean,Mathlib/AlgebraicGeometry/EllipticCurve/Singular/Basic.lean,Mathlib/AlgebraicGeometry/EllipticCurve/VariableChange.lean	3	35	['Multramate', 'acmepjz', 'erdOne', 'github-actions', 'leanprover-community-bot-assistant']	nobody	242-63082 7 months ago	242-63083 7 months ago	0-0 0 seconds
25988	Multramate author:Multramate	refactor(AlgebraicGeometry/EllipticCurve/*): replace Fin 3 with products	This PR continues the work from #24593. Original PR: https://github.com/leanprover-community/mathlib4/pull/24593	merge-conflict t-algebraic-geometry	1000/1022	Mathlib/AlgebraicGeometry/EllipticCurve/Jacobian/Basic.lean,Mathlib/AlgebraicGeometry/EllipticCurve/Jacobian/Formula.lean,Mathlib/AlgebraicGeometry/EllipticCurve/Jacobian/Point.lean,Mathlib/AlgebraicGeometry/EllipticCurve/Projective/Basic.lean,Mathlib/AlgebraicGeometry/EllipticCurve/Projective/Formula.lean,Mathlib/AlgebraicGeometry/EllipticCurve/Projective/Point.lean	6	3	['Multramate', 'github-actions', 'leanprover-community-bot-assistant']	nobody	242-62770 7 months ago	242-62770 7 months ago	18-21880 18 days
24405	mcdoll author:mcdoll	refactor(Topology/Algebra/Module/WeakDual): Clean up	- Move `Dual` and `dualPairing` lower in the import-hierachy - deduplicate `dualPairing` - Make `WeakDual` and `WeakSpace` reducible --- New version of #11500 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology large-import	146/162	Mathlib.lean,Mathlib/Analysis/Fourier/RiemannLebesgueLemma.lean,Mathlib/Analysis/InnerProductSpace/Adjoint.lean,Mathlib/Analysis/InnerProductSpace/Dual.lean,Mathlib/Analysis/LocallyConvex/WeakSpace.lean,Mathlib/Analysis/Normed/Module/Dual.lean,Mathlib/Analysis/Normed/Module/WeakDual.lean,Mathlib/Analysis/VonNeumannAlgebra/Basic.lean,Mathlib/MeasureTheory/Function/AEEqOfIntegral.lean,Mathlib/MeasureTheory/Measure/FiniteMeasure.lean,Mathlib/Topology/Algebra/Module/Dual.lean,Mathlib/Topology/Algebra/Module/WeakDual.lean,docs/overview.yaml,docs/undergrad.yaml	14	2	['github-actions', 'leanprover-community-bot-assistant']	nobody	241-28199 7 months ago	241-28200 7 months ago	0-0 0 seconds
26067	mapehe author:mapehe	feat(Topology/StoneCech): exists_continuous_surjection_from_StoneCech_to_dense_range	This lemma formalises the following version of the maximality property of the Stone–Čech compactification: If `f : α → β` is a continuous map from a topological space `α` to a Hausdorff space `β` with dense range, then there exists a continuous surjection from `StoneCech α` to `β` extending `f`. In particular, `StoneCech α` is the “largest” compact Hausdorff space into which `α` densely embeds, in the sense that any other such space is a continuous image of it. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology	18/0	Mathlib/Topology/StoneCech.lean	1	2	['github-actions', 'leanprover-community-bot-assistant']	nobody	239-44148 7 months ago	239-44148 7 months ago	20-8582 20 days
25238	Hagb author:Hagb	feat(Tactic/ComputeDegree): add support for scalar multiplication with different types	It would be able to deal with `a • (X : R[X])` where `a : S` is in a different type `S` with `[SMulZeroClass S R]`. --- - [x] depends on: #25237 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-meta new-contributor	17/5	Mathlib/Tactic/ComputeDegree.lean,MathlibTest/ComputeDegree.lean	2	3	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot']	nobody	212-41410 7 months ago	212-41410 7 months ago	0-0 0 seconds
26200	adomani author:adomani	fix: add label when landrun fails	Adds the `permission-denied` label on PRs that get blocked by landrun. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict CI	68/8	.github/build.in.yml,.github/workflows/bors.yml,.github/workflows/build.yml,.github/workflows/build_fork.yml	4	2	['github-actions', 'mathlib4-merge-conflict-bot']	nobody	210-78763 6 months ago	210-78763 6 months ago	46-52210 46 days
27451	kckennylau author:kckennylau	feat(RingTheory/Valuation): define ball, closed ball, and sphere	From the 2025 Local Class Field Theory Workshop. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-ring-theory	27/0	Mathlib/RingTheory/Valuation/Basic.lean	1	13	['JovanGerb', 'github-actions', 'kckennylau', 'mathlib4-merge-conflict-bot', 'pechersky', 'wwylele']	nobody	205-24866 6 months ago	205-24867 6 months ago	17-52359 17 days
27987	kckennylau author:kckennylau	feat(RingTheory/Valuation): define ball, closed ball, and sphere	--- The pullback PR of #26827 and #27451. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict large-import t-ring-theory	73/0	Mathlib/RingTheory/Valuation/Basic.lean	1	4	['JovanGerb', 'github-actions', 'kckennylau', 'mathlib4-merge-conflict-bot']	nobody	205-24495 6 months ago	205-24496 6 months ago	6-6455 6 days
27003	eric-wieser author:eric-wieser	chore: use `Simp.ResultQ` more often	Also uses `~q` in place of manual `isDefEq` matching. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-meta	18/22	Mathlib/Tactic/NormNum/Core.lean,Mathlib/Tactic/NormNum/Result.lean,Mathlib/Tactic/ReduceModChar.lean	3	7	['JovanGerb', 'eric-wieser', 'github-actions', 'mathlib4-merge-conflict-bot']	JovanGerb assignee:JovanGerb	203-39119 6 months ago	203-39120 6 months ago	0-0 0 seconds
25483	VTrelat author:VTrelat	chore(Data/Set/Prod, SetTheory/ZFC/Basic): add theorem prod_subset_of_prod and extend ZFC model	Required by @eric-wieser in #24281 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor t-data	103/0	Mathlib/Data/Set/Prod.lean,Mathlib/SetTheory/ZFC/Basic.lean	2	10	['Ruben-VandeVelde', 'VTrelat', 'github-actions', 'leanprover-community-bot-assistant']	nobody	203-28762 6 months ago	242-63069 7 months ago	0-0 0 seconds
25401	digama0 author:digama0	feat(Util): SuppressSorry option	See also leanprover/lean4#8611 and [#lean4 > Silent sorry @ 💬](https://leanprover.zulipchat.com/#narrow/channel/270676-lean4/topic/Silent.20sorry/near/503537964). This is a stop-gap solution while leanprover/lean4#8611 is underway, but it works about as well as any other built in option. Hooking declaration elaborators turns out to be a very powerful technique. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-meta	342/0	Mathlib.lean,Mathlib/Util/CommandElabHook.lean,Mathlib/Util/SuppressSorry.lean,MathlibTest/suppressSorry.lean	4	15	['digama0', 'eric-wieser', 'github-actions', 'mathlib4-merge-conflict-bot']	alexjbest assignee:alexjbest	202-80315 6 months ago	202-80315 6 months ago	0-0 0 seconds
28622	alreadydone author:alreadydone	chore(Mathlib): replace `=>` by `↦`	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict	51792/51792	Mathlib/Algebra/AddTorsor/Basic.lean,Mathlib/Algebra/AddTorsor/Defs.lean,Mathlib/Algebra/Algebra/Basic.lean,Mathlib/Algebra/Algebra/Bilinear.lean,Mathlib/Algebra/Algebra/Defs.lean,Mathlib/Algebra/Algebra/Equiv.lean,Mathlib/Algebra/Algebra/Hom.lean,Mathlib/Algebra/Algebra/Hom/Rat.lean,Mathlib/Algebra/Algebra/NonUnitalHom.lean,Mathlib/Algebra/Algebra/NonUnitalSubalgebra.lean,Mathlib/Algebra/Algebra/Operations.lean,Mathlib/Algebra/Algebra/Opposite.lean,Mathlib/Algebra/Algebra/Prod.lean,Mathlib/Algebra/Algebra/Rat.lean,Mathlib/Algebra/Algebra/Spectrum/Basic.lean,Mathlib/Algebra/Algebra/Spectrum/Pi.lean,Mathlib/Algebra/Algebra/Spectrum/Quasispectrum.lean,Mathlib/Algebra/Algebra/Subalgebra/Basic.lean,Mathlib/Algebra/Algebra/Subalgebra/Centralizer.lean,Mathlib/Algebra/Algebra/Subalgebra/Directed.lean,Mathlib/Algebra/Algebra/Subalgebra/IsSimpleOrder.lean,Mathlib/Algebra/Algebra/Subalgebra/Lattice.lean,Mathlib/Algebra/Algebra/Subalgebra/Matrix.lean,Mathlib/Algebra/Algebra/Subalgebra/Operations.lean,Mathlib/Algebra/Algebra/Subalgebra/Pointwise.lean,Mathlib/Algebra/Algebra/Subalgebra/Prod.lean,Mathlib/Algebra/Algebra/Subalgebra/Unitization.lean,Mathlib/Algebra/Algebra/Tower.lean,Mathlib/Algebra/Algebra/TransferInstance.lean,Mathlib/Algebra/Algebra/Unitization.lean,Mathlib/Algebra/Algebra/ZMod.lean,Mathlib/Algebra/AlgebraicCard.lean,Mathlib/Algebra/BigOperators/Associated.lean,Mathlib/Algebra/BigOperators/Expect.lean,Mathlib/Algebra/BigOperators/Fin.lean,Mathlib/Algebra/BigOperators/Finprod.lean,Mathlib/Algebra/BigOperators/Finsupp/Basic.lean,Mathlib/Algebra/BigOperators/Finsupp/Fin.lean,Mathlib/Algebra/BigOperators/Group/Finset/Basic.lean,Mathlib/Algebra/BigOperators/Group/Finset/Defs.lean,Mathlib/Algebra/BigOperators/Group/Finset/Piecewise.lean,Mathlib/Algebra/BigOperators/Group/Finset/Sigma.lean,Mathlib/Algebra/BigOperators/Group/List/Basic.lean,Mathlib/Algebra/BigOperators/Group/List/Defs.lean,Mathlib/Algebra/BigOperators/Group/List/Lemmas.lean,Mathlib/Algebra/BigOperators/Group/Multiset/Basic.lean,Mathlib/Algebra/BigOperators/Group/Multiset/Defs.lean,Mathlib/Algebra/BigOperators/GroupWithZero/Finset.lean,Mathlib/Algebra/BigOperators/Intervals.lean,Mathlib/Algebra/BigOperators/Option.lean,Mathlib/Algebra/BigOperators/Pi.lean,Mathlib/Algebra/BigOperators/Ring/Finset.lean,Mathlib/Algebra/BigOperators/Ring/Multiset.lean,Mathlib/Algebra/Category/AlgCat/Basic.lean,Mathlib/Algebra/Category/AlgCat/Limits.lean,Mathlib/Algebra/Category/AlgCat/Monoidal.lean,Mathlib/Algebra/Category/BialgCat/Basic.lean,Mathlib/Algebra/Category/BoolRing.lean,Mathlib/Algebra/Category/CoalgCat/Basic.lean,Mathlib/Algebra/Category/CoalgCat/ComonEquivalence.lean,Mathlib/Algebra/Category/FGModuleCat/Limits.lean,Mathlib/Algebra/Category/Grp/AB.lean,Mathlib/Algebra/Category/Grp/Adjunctions.lean,Mathlib/Algebra/Category/Grp/Basic.lean,Mathlib/Algebra/Category/Grp/Biproducts.lean,Mathlib/Algebra/Category/Grp/CartesianMonoidal.lean,Mathlib/Algebra/Category/Grp/Colimits.lean,Mathlib/Algebra/Category/Grp/EpiMono.lean,Mathlib/Algebra/Category/Grp/FilteredColimits.lean,Mathlib/Algebra/Category/Grp/Images.lean,Mathlib/Algebra/Category/Grp/Kernels.lean,Mathlib/Algebra/Category/Grp/LargeColimits.lean,Mathlib/Algebra/Category/Grp/LeftExactFunctor.lean,Mathlib/Algebra/Category/Grp/Limits.lean,Mathlib/Algebra/Category/Grp/Preadditive.lean,Mathlib/Algebra/Category/Grp/ZModuleEquivalence.lean,Mathlib/Algebra/Category/Grp/Zero.lean,Mathlib/Algebra/Category/GrpWithZero.lean,Mathlib/Algebra/Category/HopfAlgCat/Basic.lean,Mathlib/Algebra/Category/ModuleCat/Adjunctions.lean,Mathlib/Algebra/Category/ModuleCat/Basic.lean,Mathlib/Algebra/Category/ModuleCat/Biproducts.lean,Mathlib/Algebra/Category/ModuleCat/ChangeOfRings.lean,Mathlib/Algebra/Category/ModuleCat/Colimits.lean,Mathlib/Algebra/Category/ModuleCat/EpiMono.lean,Mathlib/Algebra/Category/ModuleCat/FilteredColimits.lean,Mathlib/Algebra/Category/ModuleCat/Images.lean,Mathlib/Algebra/Category/ModuleCat/Injective.lean,Mathlib/Algebra/Category/ModuleCat/Kernels.lean,Mathlib/Algebra/Category/ModuleCat/Limits.lean,Mathlib/Algebra/Category/ModuleCat/Monoidal/Basic.lean,Mathlib/Algebra/Category/ModuleCat/Monoidal/Closed.lean,Mathlib/Algebra/Category/ModuleCat/Monoidal/Symmetric.lean,Mathlib/Algebra/Category/ModuleCat/Presheaf.lean,Mathlib/Algebra/Category/ModuleCat/Presheaf/Abelian.lean,Mathlib/Algebra/Category/ModuleCat/Presheaf/Colimits.lean,Mathlib/Algebra/Category/ModuleCat/Presheaf/Limits.lean,Mathlib/Algebra/Category/ModuleCat/Presheaf/Pushforward.lean,Mathlib/Algebra/Category/ModuleCat/Presheaf/Sheafify.lean,Mathlib/Algebra/Category/ModuleCat/Products.lean	3838	4	['github-actions', 'mathlib4-merge-conflict-bot']	nobody	196-83795 6 months ago	196-83796 6 months ago	0-83357 23 hours
28626	alreadydone author:alreadydone	chore(Archive, Counterexamples): replace => by ↦	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict	288/288	Archive/Arithcc.lean,Archive/Examples/IfNormalization/Result.lean,Archive/Examples/IfNormalization/WithoutAesop.lean,Archive/Examples/PropEncodable.lean,Archive/Imo/Imo1959Q1.lean,Archive/Imo/Imo1960Q1.lean,Archive/Imo/Imo1962Q4.lean,Archive/Imo/Imo1972Q5.lean,Archive/Imo/Imo1977Q6.lean,Archive/Imo/Imo1981Q3.lean,Archive/Imo/Imo1987Q1.lean,Archive/Imo/Imo1988Q6.lean,Archive/Imo/Imo1994Q1.lean,Archive/Imo/Imo1998Q2.lean,Archive/Imo/Imo2001Q2.lean,Archive/Imo/Imo2006Q3.lean,Archive/Imo/Imo2006Q5.lean,Archive/Imo/Imo2008Q2.lean,Archive/Imo/Imo2008Q4.lean,Archive/Imo/Imo2011Q3.lean,Archive/Imo/Imo2013Q1.lean,Archive/Imo/Imo2019Q1.lean,Archive/Imo/Imo2024Q5.lean,Archive/MiuLanguage/Basic.lean,Archive/MiuLanguage/DecisionSuf.lean,Archive/OxfordInvariants/Summer2021/Week3P1.lean,Archive/Sensitivity.lean,Archive/Wiedijk100Theorems/AbelRuffini.lean,Archive/Wiedijk100Theorems/AreaOfACircle.lean,Archive/Wiedijk100Theorems/AscendingDescendingSequences.lean,Archive/Wiedijk100Theorems/BallotProblem.lean,Archive/Wiedijk100Theorems/BirthdayProblem.lean,Archive/Wiedijk100Theorems/BuffonsNeedle.lean,Archive/Wiedijk100Theorems/CubingACube.lean,Archive/Wiedijk100Theorems/FriendshipGraphs.lean,Archive/Wiedijk100Theorems/Konigsberg.lean,Archive/Wiedijk100Theorems/Partition.lean,Archive/Wiedijk100Theorems/SumOfPrimeReciprocalsDiverges.lean,Archive/ZagierTwoSquares.lean,Counterexamples/AharoniKorman.lean,Counterexamples/CanonicallyOrderedCommSemiringTwoMul.lean,Counterexamples/CharPZeroNeCharZero.lean,Counterexamples/CliffordAlgebraNotInjective.lean,Counterexamples/DirectSumIsInternal.lean,Counterexamples/GameMultiplication.lean,Counterexamples/Girard.lean,Counterexamples/HomogeneousPrimeNotPrime.lean,Counterexamples/MapFloor.lean,Counterexamples/MonicNonRegular.lean,Counterexamples/Phillips.lean,Counterexamples/Pseudoelement.lean,Counterexamples/QuadraticForm.lean,Counterexamples/SorgenfreyLine.lean,Counterexamples/ZeroDivisorsInAddMonoidAlgebras.lean	54	2	['github-actions', 'mathlib4-merge-conflict-bot']	nobody	195-26521 6 months ago	195-26522 6 months ago	2-48353 2 days
13795	astrainfinita author:astrainfinita	perf(Algebra/{Group, GroupWithZero, Ring}/InjSurj): reduce everything	--- - [ ] depends on: #15192 - [ ] depends on: #15476 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	340/194	Mathlib/Algebra/Equiv/TransferInstance.lean,Mathlib/Algebra/Group/InjSurj.lean,Mathlib/Algebra/GroupWithZero/Action/Defs.lean,Mathlib/Algebra/GroupWithZero/Action/End.lean,Mathlib/Algebra/GroupWithZero/InjSurj.lean,Mathlib/Algebra/Module/Defs.lean,Mathlib/Algebra/Module/RingHom.lean,Mathlib/Algebra/Ring/InjSurj.lean,scripts/noshake.json	9	37	['MichaelStollBayreuth', 'astrainfinita', 'eric-wieser', 'github-actions', 'leanprover-bot', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot', 'mattrobball']	nobody	194-32592 6 months ago	323-47597 10 months ago	0-0 0 seconds
28150	Equilibris author:Equilibris	chore: clean up proofs typevec proofs	While adding variable universe corecs I found a lot of theorems in typevec that could do with a bit of a clean-up --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor t-data	24/26	Mathlib/Data/TypeVec.lean	1	7	['Equilibris', 'alexkeizer', 'github-actions', 'mathlib4-merge-conflict-bot']	nobody	193-80237 6 months ago	193-80238 6 months ago	13-49738 13 days
27403	MoritzBeroRoos author:MoritzBeroRoos	fix: replace probably erroneous usage of ⬝ (with old \cdot) by · (with \centerdot)	Discussion at [zulip](https://leanprover.zulipchat.com/#narrow/channel/270676-lean4/topic/.5Ccdot.20!.3D.20.5Ccenterdot). Currently the abbreviations \cdot and \centerdot resolve to different, with the naked eye nearly undistinguishable symbols (despite the c in cdot surely standing for center..). This pr replaces instances of ⬝ where · was probably meant. All of the replacement is in comments, except for the file bench_summary.lean which is used for priting the github benchmark results. Since this file is about scientific notation of numbers, sure · was meant to be used, not a rectangle. [Related](https://github.com/leanprover-community/mathlib4/pull/27399) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor	195/195	Mathlib/Algebra/ContinuedFractions/Computation/Approximations.lean,Mathlib/Algebra/DirectSum/Idempotents.lean,Mathlib/Algebra/Lie/Derivation/Basic.lean,Mathlib/Algebra/Module/Equiv/Basic.lean,Mathlib/AlgebraicGeometry/EllipticCurve/DivisionPolynomial/Basic.lean,Mathlib/Analysis/Analytic/Constructions.lean,Mathlib/Analysis/CStarAlgebra/CStarMatrix.lean,Mathlib/Analysis/Calculus/ContDiff/Basic.lean,Mathlib/Analysis/Calculus/ContDiff/Bounds.lean,Mathlib/Analysis/Calculus/FDeriv/Symmetric.lean,Mathlib/Analysis/Fourier/FourierTransformDeriv.lean,Mathlib/Analysis/InnerProductSpace/Dual.lean,Mathlib/Analysis/InnerProductSpace/PiL2.lean,Mathlib/Analysis/Normed/Unbundled/InvariantExtension.lean,Mathlib/Analysis/SpecialFunctions/Complex/CircleAddChar.lean,Mathlib/Combinatorics/Configuration.lean,Mathlib/Combinatorics/SimpleGraph/AdjMatrix.lean,Mathlib/Combinatorics/SimpleGraph/LapMatrix.lean,Mathlib/Data/Matrix/Block.lean,Mathlib/Data/Matrix/ConjTranspose.lean,Mathlib/Data/Matrix/Hadamard.lean,Mathlib/Data/Matrix/Mul.lean,Mathlib/Data/Matrix/Notation.lean,Mathlib/Data/Matrix/Reflection.lean,Mathlib/Data/Matrix/RowCol.lean,Mathlib/Data/Matrix/Vec.lean,Mathlib/FieldTheory/PurelyInseparable/PerfectClosure.lean,Mathlib/Geometry/Manifold/GroupLieAlgebra.lean,Mathlib/GroupTheory/Coxeter/Matrix.lean,Mathlib/LinearAlgebra/CrossProduct.lean,Mathlib/LinearAlgebra/Matrix/BilinearForm.lean,Mathlib/LinearAlgebra/Matrix/DotProduct.lean,Mathlib/LinearAlgebra/Matrix/Nondegenerate.lean,Mathlib/LinearAlgebra/Matrix/Orthogonal.lean,Mathlib/LinearAlgebra/Matrix/PosDef.lean,Mathlib/LinearAlgebra/Matrix/SchurComplement.lean,Mathlib/LinearAlgebra/Matrix/SesquilinearForm.lean,Mathlib/LinearAlgebra/Matrix/Trace.lean,Mathlib/LinearAlgebra/Multilinear/Basic.lean,Mathlib/LinearAlgebra/PerfectPairing/Matrix.lean,Mathlib/LinearAlgebra/Projectivization/Constructions.lean,Mathlib/NumberTheory/NumberField/ProductFormula.lean,Mathlib/NumberTheory/SiegelsLemma.lean,Mathlib/RingTheory/DividedPowers/SubDPIdeal.lean,Mathlib/SetTheory/Ordinal/Veblen.lean,Mathlib/Topology/Algebra/Module/Equiv.lean,Mathlib/Topology/Homeomorph/Lemmas.lean,Mathlib/Topology/Instances/Matrix.lean,scripts/bench_summary.lean	49	5	['eric-wieser', 'github-actions', 'grunweg', 'leanprover-community-bot-assistant']	nobody	193-59557 6 months ago	216-35479 7 months ago	7-54661 7 days
28042	kckennylau author:kckennylau	feat(Topology/ValuativeRel): a topological basis indexed by pairs of elements	--- The pullback PR of #27314 and #27163. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-ring-theory	140/23	Mathlib/RingTheory/Valuation/ValuativeRel.lean,Mathlib/Topology/Algebra/Valued/ValuativeRel.lean	2	3	['github-actions', 'grunweg', 'mathlib4-merge-conflict-bot']	nobody	193-59511 6 months ago	193-59511 6 months ago	7-4998 7 days
27399	MoritzBeroRoos author:MoritzBeroRoos	chore: replace every usage of ⬝ᵥ (with old \cdot) by ·ᵥ (with \centerdot)	Discussion at [zulip](https://leanprover.zulipchat.com/#narrow/channel/270676-lean4/topic/.5Ccdot.20!.3D.20.5Ccenterdot). Currently the abbreviations `\cdot` and `\centerdot` resolve to different, with the naked eye nearly undistinguishable symbols (despite the c in cdot surely standing for `center`..): - `\cdot` gives ⬝ [U+2B1D](https://www.compart.com/en/unicode/U+2B1D) "Black Very Small Square" - `\centerdot` gives · [U+00B7](https://www.compart.com/en/unicode/U+00B7) "Middle Dot" Mathlib mostly uses the `\centerdot` variant, except for the dotProduct notation and some probably unsuspecting people wanting \centerdot but getting \cdot in their comments and 6 uses of a notation using the raw `\cdot` without any subscript at `Mathlib\Topology\Homotopy\Product.lean`. This PR replaces the dot product `⬝ᵥ` with its `\centerdot` counterpart `·ᵥ`. The related PR [here](https://github.com/leanprover/vscode-lean4/pull/639) can then overwrite the `\cdot` abbreviation, to produce the same symbol as the `centerdot` abbreviation does. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor	133/133	Mathlib/Analysis/CStarAlgebra/CStarMatrix.lean,Mathlib/Analysis/InnerProductSpace/PiL2.lean,Mathlib/Combinatorics/Configuration.lean,Mathlib/Combinatorics/SimpleGraph/AdjMatrix.lean,Mathlib/Combinatorics/SimpleGraph/LapMatrix.lean,Mathlib/Data/Matrix/Block.lean,Mathlib/Data/Matrix/ConjTranspose.lean,Mathlib/Data/Matrix/Hadamard.lean,Mathlib/Data/Matrix/Mul.lean,Mathlib/Data/Matrix/Notation.lean,Mathlib/Data/Matrix/Reflection.lean,Mathlib/Data/Matrix/RowCol.lean,Mathlib/Data/Matrix/Vec.lean,Mathlib/LinearAlgebra/CrossProduct.lean,Mathlib/LinearAlgebra/Matrix/BilinearForm.lean,Mathlib/LinearAlgebra/Matrix/DotProduct.lean,Mathlib/LinearAlgebra/Matrix/Nondegenerate.lean,Mathlib/LinearAlgebra/Matrix/Orthogonal.lean,Mathlib/LinearAlgebra/Matrix/PosDef.lean,Mathlib/LinearAlgebra/Matrix/SchurComplement.lean,Mathlib/LinearAlgebra/Matrix/SesquilinearForm.lean,Mathlib/LinearAlgebra/Matrix/Trace.lean,Mathlib/LinearAlgebra/PerfectPairing/Matrix.lean,Mathlib/LinearAlgebra/Projectivization/Constructions.lean,Mathlib/Topology/Instances/Matrix.lean	25	6	['MoritzBeroRoos', 'eric-wieser', 'github-actions', 'leanprover-community-bot-assistant']	nobody	193-21389 6 months ago	216-35480 7 months ago	7-62439 7 days
28148	kckennylau author:kckennylau	feat(Matrix): Simproc and Rw-proc for Matrix Transpose	Co-authored by Aaron Liu. ```lean example : !![1, 2, 3; 4, 5, 6]ᵀ = !![1, 4; 2, 5; 3, 6] := by rw [transpose_of% 2 3] example : !![1, 2, 3; 4, 5, 6]ᵀ = !![1, 4; 2, 5; 3, 6] := by rw [transpose_of] example : !![1, 2, 3; 4, 5, 6]ᵀ = !![1, 4; 2, 5; 3, 6] := by simp only [matrix_transpose] ``` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-meta	267/8	Mathlib.lean,Mathlib/Data/Matrix/Notation.lean,Mathlib/LinearAlgebra/UnitaryGroup.lean,Mathlib/Tactic.lean,Mathlib/Tactic/Simproc/Matrix.lean,MathlibTest/Simproc/Matrix.lean,MathlibTest/matrix.lean,scripts/noshake.json	8	32	['eric-wieser', 'github-actions', 'kckennylau', 'mathlib4-merge-conflict-bot', 'plp127']	eric-wieser assignee:eric-wieser	188-64723 6 months ago	188-64724 6 months ago	16-54453 16 days
26908	robin-carlier author:robin-carlier	feat(CategoryTheory/Monoidal/DayConvolution): alternative ext principle for unitors	Currently, our infrastructure for left/right unitors for Day convolution of functors `C ⥤ V` do not have satisfactory extensionality principle: the current way to characterize morphisms out of `U ⊛ F` is the default extensionality principle for Day convolution, which characterizes first such functors via functors out of `U ⊠ F`. Left unitors are then obtained using the fact `U ⊠ F` is a left Kan extension of a functor from `PUnit × C` (which is equivalent to `C`) but we did not record on its own this principle. Using the transitivity of left Kan extensions proved in #26899, we directly exhibit `U ⊛ F` as a left Kan extension of `F ⋙ tensorLeft (𝟙_ V)` along `tensorLeft (𝟙_ C)`. The unit of this Kan extension is composed exactly of the morphisms that appear in the [characterization of left unitors](https://leanprover-community.github.io/mathlib4_docs/Mathlib/CategoryTheory/Monoidal/DayConvolution.html#CategoryTheory.MonoidalCategory.DayConvolutionUnit.leftUnitor_hom_unit_app). We also slightly generalize the instances that express that external products with unitors are left Kan extensions, so that they can be used when taking external products with more complicated functors than currently. This is again useful when chaining extensionality lemmas for morphisms out of terms of the form `(F ⊛ U) ⊛ G`. We prove a similar thing for right unitors With this, it should be possible to have a much more satisfactory way of working with Day convolutions: this allows to "elimiinate" units without ending up with terms in an external product. --- - [ ] depends on: #26899 - [ ] depends on: #26906 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-category-theory	307/18	Mathlib/CategoryTheory/Functor/KanExtension/Basic.lean,Mathlib/CategoryTheory/Monoidal/DayConvolution.lean	2	4	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	177-24669 5 months ago	177-24670 5 months ago	0-1812 30 minutes
27150	robin-carlier author:robin-carlier	feat(CategoryTheory/Monoidal/DayConvolution): constructors for braided and symmetric structure on day convolutions monoidal categories	Following the pattern in #27119, we give API to construct `BraidedCategory` and `SymmetricCategory` structures on a monoidal category equipped with a `LawfulDayConvolutionMonoidalCategoryStruct`. To achieve this, we introduce an other type class `LawfulDayConvolutionBraidedCategoryStruct` that bundles an associator isomorphism that behaves like the one constructed for functors in #27067. We provide a noncomputable constructor for this typeclass that takes as input fullness of the "realization" functor to a category of functors, and we show that the typeclasses are sufficient to define the desired structures. --- - [x] depends on: #27067 - [x] depends on: #26820 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-category-theory	826/9	Mathlib/CategoryTheory/Monoidal/DayConvolution.lean,Mathlib/CategoryTheory/Monoidal/DayConvolution/Braided.lean	2	5	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	177-19708 5 months ago	177-20496 5 months ago	0-1002 16 minutes
27119	robin-carlier author:robin-carlier	feat(CategoryTheory/Monoidal/DayConvolution): constructors for closed monoidal day convolution monoidal structures	Following the pattern introduced in #26798 and #26820 and using results of #26879, we introduce a typeclass `LawfulDayConvolutionClosedMonoidalCategoryStruct` that encodes the data needed on a `LawfulDayConvolutionMonoidalCategoryStruct` to define well-behaved internal homs. We give a constructor assuming existence of relevant ends, and prove that this data defines a `MonoidalClosed` instance on the monoidal category structures one can deduce from `LawfulDayConvolutionMonoidalCategoryStruct`. --- - [x] depends on: #27079 - [x] depends on: #27091 - [x] depends on: #26879 - [x] depends on: #26820 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-category-theory	900/9	Mathlib/CategoryTheory/Monoidal/DayConvolution.lean,Mathlib/CategoryTheory/Monoidal/DayConvolution/Closed.lean	2	6	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	176-33559 5 months ago	177-20493 5 months ago	0-1 1 second
28623	gilesgshaw author:gilesgshaw	feat(Logic/Basic): minor additions and simplification of proofs	Add new theorems and simplify proofs. Specifically, we add the family of related theorems `apply_dite_iff_exists`, `apply_dite_iff_forall`, `apply_ite_iff_and` and `apply_ite_iff_or`. For each other 'family' of theorems in the file that is analogous to the above, we do the following - Simplify proofs where possible, e.g. by appealing to the new theorems - Complete the family, if any of the corresponding four are missing - Rename to ensure consistency with the above pattern ---	merge-conflict t-logic new-contributor	83/55	Archive/Examples/IfNormalization/Result.lean,Archive/Examples/IfNormalization/WithoutAesop.lean,Mathlib/Algebra/ContinuedFractions/Computation/Translations.lean,Mathlib/Algebra/MvPolynomial/Variables.lean,Mathlib/Algebra/Notation/Indicator.lean,Mathlib/LinearAlgebra/Matrix/Rank.lean,Mathlib/Logic/Basic.lean,Mathlib/MeasureTheory/Measure/WithDensity.lean,Mathlib/SetTheory/Ordinal/Notation.lean	9	12	['eric-wieser', 'gilesgshaw', 'github-actions', 'mathlib4-merge-conflict-bot', 'plp127']	awainverse assignee:awainverse	176-27420 5 months ago	176-27421 5 months ago	21-3001 21 days
27933	grunweg author:grunweg	chore(OrdNode): format code example in code blocks	Wrap them in code blocks (and unindent them; that indentation is not needed any more). This also avoids warnings from the linter in #27898. ------- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-data	459/212	Mathlib/Data/Ordmap/Ordnode.lean	1	4	['eric-wieser', 'github-actions', 'grunweg', 'mathlib4-merge-conflict-bot']	nobody	172-64453 5 months ago	172-64454 5 months ago	39-69478 39 days
26154	ADedecker author:ADedecker	refactor: add refactored APIs for algebraic filter bases	This PR continues the work from #18437. Original PR: https://github.com/leanprover-community/mathlib4/pull/18437	merge-conflict t-topology	651/0	Mathlib.lean,Mathlib/Topology/Algebra/FilterBasis.lean,Mathlib/Topology/Algebra/FilterBasisNew.lean,Mathlib/Topology/Algebra/Nonarchimedean/Bases.lean,Mathlib/Topology/Algebra/Nonarchimedean/BasesNew.lean	5	3	['ADedecker', 'github-actions', 'mathlib4-merge-conflict-bot']	PatrickMassot assignee:PatrickMassot	170-39664 5 months ago	170-39665 5 months ago	87-79752 87 days
29330	plp127 author:plp127	chore: define `Fin.cycleIcc` with conditions	Redefine `Fin.cycleIcc` using conditionals instead of composing existing `Fin` operations together. Its worst-case runtime drops from O(n) to O(1). As a bonus, the definition no longer needs explaining. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-group-theory	61/68	Mathlib/GroupTheory/Perm/Fin.lean	1	10	['JovanGerb', 'eric-wieser', 'github-actions', 'mathlib4-merge-conflict-bot', 'plp127', 'tb65536']	nobody	161-51261 5 months ago	161-51262 5 months ago	20-39203 20 days
21950	erdOne author:erdOne	feat(NumberTheory/Padics): the completion of `ℚ` at a finite place is `ℚ_[p]`	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-number-theory	253/1	Mathlib.lean,Mathlib/Algebra/GroupWithZero/WithZero.lean,Mathlib/NumberTheory/Padics/HeightOneSpectrum.lean,Mathlib/NumberTheory/Padics/PadicNumbers.lean,Mathlib/Topology/Algebra/Valued/WithVal.lean,Mathlib/Topology/Algebra/WithZeroMulInt.lean,Mathlib/Topology/Algebra/WithZeroTopology.lean	7	33	['Ruben-VandeVelde', 'erdOne', 'faenuccio', 'github-actions', 'leanprover-community-bot-assistant', 'pechersky', 'smmercuri', 'xroblot']	nobody	159-26371 5 months ago	240-26308 7 months ago	0-0 0 seconds
27214	robin-carlier author:robin-carlier	feat(CategoryTheory/Limits/Shapes/Pullback/Categorical): Categorical pullback squares	In this PR, we give the definition and first basic properties of categorical pullback squares. Using our previous work on `CategoricalPullback`, we define a typeclass `CatPullbackSquare T L R B` that asserts that a given `CatCommSq T L R B` is a "pullback square": this is the data of a chosen adjoint equivalence to the canonical functor from the top left corner of the square to the categorical pulback of its leg. Using this equivalence, be derive a universal property for functors from `X`with values in the top left corner of the square: they are equivalent to `CatCommSqOver R B X`, the category of categorical commutative squares over the cospan `R, B` with top left corner `X`. We prove some coherence result for this equivalence, most notably an isomorphism that, given `S : CatCommSqOver R B X`, bundles the two commutative triangles formed by the induced functor, and the coherence between the squares that these isomorphisms satisfy: this is conveniently bundled in the data of a single isomorphisms of `CatCommSqOver R B X`. Finally, we provide a `Prop`-class `IsCatPullbackSquare` that merely asserts the existence (via `Nonempty`) of the relevant data: we show that it is tautotogically equivalent to the propopsition that the canonical functor to the categorical pullback is an equivalence. --- - [ ] depends on: #26679 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-category-theory	786/1	Mathlib.lean,Mathlib/CategoryTheory/Limits/Shapes/Pullback/Categorical/Basic.lean,Mathlib/CategoryTheory/Limits/Shapes/Pullback/Categorical/Square.lean	3	3	['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	156-16453 5 months ago	156-16454 5 months ago	0-5521 1 hour
26466	robin-carlier author:robin-carlier	feat(AlgebraicTopology/SimplexCategory/Augmented): the canonical monoid object in the augmented simplex category	Show that in the augmented simplex category, `⦋0⦌` is an internal monoid object. Future work will show that this is in fact the universal monoid object: for any monoidal category `C`, evaluation at `⦋0⦌` induces an equivalence of categories between `Mon_ C` and the category of monoidal functors from `AugmentedSimplexCategory` to `C`. The resulting augmented cosimplicial object one gets from this construction is sometimes called the "monoidal bar construction" attached to a monoid. This PR was split from #25743. --- - [ ] depends on: #25743 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-category-theory t-algebraic-topology	571/111	Mathlib.lean,Mathlib/AlgebraicTopology/SimplexCategory/Augmented.lean,Mathlib/AlgebraicTopology/SimplexCategory/Augmented/Basic.lean,Mathlib/AlgebraicTopology/SimplexCategory/Augmented/Mon_.lean,Mathlib/AlgebraicTopology/SimplexCategory/Augmented/Monoidal.lean,Mathlib/AlgebraicTopology/SimplexCategory/Basic.lean	6	4	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	155-35855 5 months ago	155-35857 5 months ago	0-1708 28 minutes
26578	robin-carlier author:robin-carlier	feat(CategoryTheory/Limits/Pullbacks/Categorical/CatCospanTransform): adjunctions of categorical cospans	We build upon the bicategory-like structure developed in #26447 and #26412 to define the notion of adjunctions of categorical cospans. This is a structure encoding the data of two `CatCospanTransform`s, along with the usual unit and counit morphisms as part of the data, satisfying the usual left and right triangle identities. We provide basic API for these, such as extracting adjunctions between individual components. We also provide a proof that the notion satisfies a "coherence": with our chosen constructor, the forward direction of the structure `CatCommSq` on the left adjoints correspond to the inverse of the square for the right adjoints through `mateEquiv`. These adjunctions will be used as a substrate for defining equivalences of categorical cospans in a future PR: such an equivalence will be a structure extending a `CatCospanAdjunction` with isomorphisms data on the unit and co-unit (we will however provide alternative constructors in sync with the constructor for equivalences of categories). --- - [x] depends on: #26447 - [x] depends on: #26547 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-category-theory large-import	205/0	Mathlib/CategoryTheory/Limits/Shapes/Pullback/Categorical/CatCospanTransform.lean	1	5	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	154-39080 5 months ago	154-42052 5 months ago	0-625 10 minutes
23621	astrainfinita author:astrainfinita	chore: deprecate `LinearOrderedComm{Monoid, Group}WithZero`	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) - [x] depends on: #20676	merge-conflict t-algebra t-order label:t-algebra$	261/205	Archive/Imo/Imo1998Q2.lean,Counterexamples/LinearOrderWithPosMulPosEqZero.lean,Mathlib/Algebra/Order/Field/Canonical.lean,Mathlib/Algebra/Order/Field/Rat.lean,Mathlib/Algebra/Order/Floor/Ring.lean,Mathlib/Algebra/Order/GroupWithZero/Canonical.lean,Mathlib/Algebra/Order/GroupWithZero/Finset.lean,Mathlib/Algebra/Order/Hom/Monoid.lean,Mathlib/Algebra/Order/Nonneg/Field.lean,Mathlib/Algebra/Order/Nonneg/Ring.lean,Mathlib/Algebra/Order/Ring/Nat.lean,Mathlib/Combinatorics/Additive/PluenneckeRuzsa.lean,Mathlib/Combinatorics/SimpleGraph/Triangle/Basic.lean,Mathlib/Data/ENNReal/Basic.lean,Mathlib/Data/NNRat/Lemmas.lean,Mathlib/Data/NNReal/Defs.lean,Mathlib/Data/Rat/Cast/Order.lean,Mathlib/FieldTheory/IntermediateField/Adjoin/Defs.lean,Mathlib/FieldTheory/RatFunc/AsPolynomial.lean,Mathlib/GroupTheory/ArchimedeanDensely.lean,Mathlib/NumberTheory/EllipticDivisibilitySequence.lean,Mathlib/NumberTheory/FunctionField.lean,Mathlib/NumberTheory/Ostrowski.lean,Mathlib/RingTheory/Valuation/Archimedean.lean,Mathlib/RingTheory/Valuation/Basic.lean,Mathlib/RingTheory/Valuation/ExtendToLocalization.lean,Mathlib/RingTheory/Valuation/Integers.lean,Mathlib/RingTheory/Valuation/Integral.lean,Mathlib/RingTheory/Valuation/Minpoly.lean,Mathlib/RingTheory/Valuation/Quotient.lean,Mathlib/RingTheory/Valuation/RankOne.lean,Mathlib/RingTheory/Valuation/ValExtension.lean,Mathlib/RingTheory/Valuation/ValuationRing.lean,Mathlib/RingTheory/Valuation/ValuationSubring.lean,Mathlib/SetTheory/Cardinal/Order.lean,Mathlib/Topology/Algebra/Valued/LocallyCompact.lean,Mathlib/Topology/Algebra/Valued/NormedValued.lean,Mathlib/Topology/Algebra/Valued/ValuationTopology.lean,Mathlib/Topology/Algebra/Valued/ValuedField.lean,Mathlib/Topology/Algebra/Valued/WithVal.lean,Mathlib/Topology/Algebra/WithZeroTopology.lean,Mathlib/Topology/UnitInterval.lean,MathlibTest/instance_diamonds.lean,scripts/noshake.json	44	n/a	['YaelDillies', 'astrainfinita', 'github-actions', 'grunweg', 'leanprover-bot', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot']	kbuzzard assignee:kbuzzard	151-20795 5 months ago	unknown	unknown
27990	kckennylau author:kckennylau	feat(Counterexamples): a nontrivial valuation with discrete topology	This file constructs a valuation on `K[X]` satisfying `IsValuativeTopology K[X] ∧ Nonempty (valuation K[X]).RankOne ∧ IsNontrivial K[X] ∧ DiscreteTopology K[X]`, and proves that `IsValuativeTopology F ∧ IsNontrivial F ∧ DiscreteTopology F` is not possible if `F` is a field. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-ring-theory	172/0	Counterexamples.lean,Counterexamples/DiscreteTopologyWithNontrivialValuation.lean	2	n/a	['github-actions', 'grunweg', 'kckennylau', 'mathlib4-merge-conflict-bot', 'pechersky']	nobody	143-22926 4 months ago	unknown	unknown
28132	dupuisf author:dupuisf	feat: preliminary `grind` tags for `IsUnit`	This PR adds preliminary `grind` tags for the `IsUnit` predicate. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	61/17	Mathlib/Algebra/Group/Action/Units.lean,Mathlib/Algebra/Group/Units/Defs.lean,Mathlib/Algebra/GroupWithZero/Units/Basic.lean,Mathlib/Algebra/Ring/Units.lean,Mathlib/Analysis/CStarAlgebra/ContinuousFunctionalCalculus/Order.lean,Mathlib/Analysis/SpecialFunctions/ContinuousFunctionalCalculus/Rpow/Basic.lean	6	3	['github-actions', 'mathlib4-merge-conflict-bot']	kim-em assignee:kim-em	119-85924 3 months ago	119-85925 3 months ago	80-71575 80 days
26827	pechersky author:pechersky	feat(Analysis/Normed/ValuativeRel): helper instance for NormedField	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) - [x] depends on: #26713 - [x] depends on: #26826	merge-conflict t-number-theory t-analysis t-algebra label:t-algebra$	211/27	Mathlib.lean,Mathlib/Analysis/Normed/ValuativeRel.lean,Mathlib/Topology/Algebra/Valued/ValuativeRel.lean	3	34	['ADedecker', 'adamtopaz', 'erdOne', 'github-actions', 'kbuzzard', 'kckennylau', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'pechersky']	kbuzzard assignee:kbuzzard	112-28128 3 months ago	112-28128 3 months ago	127-58875 127 days
22662	plp127 author:plp127	feat: Localization.Away.lift (computably)	This PR adds `Localization.Away.lift'` and `Localization.Away.lift`, computable alternatives to `Localization.awayLift`. --- - [x] depends on: #24791 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	74/0	Mathlib/RingTheory/Localization/Away/Basic.lean	1	18	['eric-wieser', 'github-actions', 'grunweg', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'plp127', 'vihdzp']	kim-em assignee:kim-em	105-50787 3 months ago	105-50788 3 months ago	0-0 0 seconds
24850	pechersky author:pechersky	feat(Topology/UniformSpace/Ultra): uniform spaces induced by pseudometrics are ultra if system is ultra	Any uniform space has a natural system of pseudometrics definable on it, comprised of those pseudometrics constructed from a descending chain of equivalence relation entourages. In a nonarchimedean uniformity, this pseudometric system induces the uniformity. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) - [x] depends on: #23111	merge-conflict t-topology	509/1	Mathlib.lean,Mathlib/Topology/MetricSpace/BundledFun.lean,Mathlib/Topology/UniformSpace/Ultra/Pseudometrizable.lean	3	9	['ADedecker', 'fpvandoorn', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'pechersky']	urkud assignee:urkud	105-50615 3 months ago	105-50616 3 months ago	0-0 0 seconds
25974	scholzhannah author:scholzhannah	feat(Topology/Compactness/CompactlyCoherentSpace): compact coherentification (k-ification)	This PR defines the notion of turning an arbitrary topological space into a compactly coherent space. Compactly coherent spaces are commonly referred to as "compactly generated spaces" or "k-spaces" in the literature while the operation of turning a space into such as space is called the "k-ification". There are however three different notions that are described with this name. To disambiguate we use the names "compactly coherent space" and "compactcoherentification" here. See [this wikipedia page](https://en.wikipedia.org/wiki/Compactly_generated_space) for an explanation of these notions. This PR continues the work from #25318. Original PR: https://github.com/leanprover-community/mathlib4/pull/25318 Co-authored-by: Floris van Doorn	merge-conflict t-topology large-import	174/5	Mathlib/Topology/Compactness/CompactlyCoherentSpace.lean	1	5	['github-actions', 'joelriou', 'mathlib4-merge-conflict-bot', 'scholzhannah']	ADedecker assignee:ADedecker	105-50447 3 months ago	105-50448 3 months ago	148-47112 148 days
26914	quangvdao author:quangvdao	feat(Data/PFunctor/Univariate): more definitions for univariate `PFunctor`	This PR defines several basic definitions of `PFunctor`, including zero, one, constants, monomials, coproduct (sum), product, sigma, pi, tensor product, universe lifting, and equivalence. We also add: (1) simple lemmas connecting the basic definitions, (2) an automatically derived ext lemma for `PFunctor` via `@[ext]` attribute Some things I'm not clear on: - I define `HAdd` and `HMul` instances for coproduct and product of poly functors having different universe levels. Should I also define `Add` and `Mul` instances for poly functors having the same universe level? - Is it ok to define notation for tensor product, i.e. `@[inherit_doc] scoped infixr:80 " ⊗ " => tensor`? I'm worried it might clash with other notation. - Need a double-check on the priority of notation. Some future definitions to add: - Various equivalences arising from arithmetic identities, e.g., `P + 0 ≃ₚ P`. - Definitions of Lenses and Charts (each of them will be a file or even a folder) - Exponential objects (corresponding to both `prod` and `tensor`) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-data	144/5	Mathlib/Data/PFunctor/Univariate/Basic.lean	1	20	['alexkeizer', 'eric-wieser', 'github-actions', 'mathlib4-merge-conflict-bot', 'quangvdao']	eric-wieser assignee:eric-wieser	105-50093 3 months ago	105-50094 3 months ago	133-25807 133 days
27534	PierreQuinton author:PierreQuinton	feat: a typeclass for `sSup`/`sInf` to be lawful	Adds lawful infima and suprema type classes. A preorder with lawful suprema: whenever a set has a least upper bound, `sSup` returns a least upper bound for that set. A preorder with lawful infima: whenever a set has a greatest lower bound, `sInf` returns a greastest lower bound for that set. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-order	121/8	Mathlib.lean,Mathlib/Order/CompleteLattice/Defs.lean,Mathlib/Order/LawfulSupInf.lean	3	26	['PierreQuinton', 'YaelDillies', 'github-actions', 'mathlib4-merge-conflict-bot', 'plp127', 'vihdzp']	YaelDillies assignee:YaelDillies	105-49930 3 months ago	105-49931 3 months ago	114-58354 114 days
28125	nonisomorphiclinearmap author:nonisomorphiclinearmap	feat(Combinatorics): basic definition of simplicial complexes	This PR introduces the basic definition of a finite (abstract) simplicial complex, located in Mathlib/Combinatorics/SimplicialComplex/Basic.lean. --- This is our first contribution to mathlib. This work was done as part of the Fields Institute Summer Undergraduate Program on formalization in topological combinatorics. Eventually, we aim to formalize Lovasz's proof of the Kneser Conjecture and this is a small stepping stone in that direction. Some other commits will shortly depend on this one. We would like to acknowledge the Fields Institute for Research in Mathematical Sciences for their sponsorship. We would also like to thank our supervisors, Professor Chris Kapulkin and Mr. Daniel Carranza, for their guidance and support throughout this project. We would also like to thank our group members Tom Lindquist and Quang Minh Nguyen for our fruitful discussions.	merge-conflict t-combinatorics new-contributor	374/0	Mathlib.lean,Mathlib/Combinatorics/SimplicialComplex/Basic.lean,Mathlib/Combinatorics/SimplicialComplex/Category.lean,Mathlib/Combinatorics/SimplicialComplex/FacePoset.lean,Mathlib/Combinatorics/SimplicialComplex/Hom.lean	5	2	['github-actions', 'mathlib4-merge-conflict-bot']	awainverse assignee:awainverse	105-49788 3 months ago	105-49789 3 months ago	102-43516 102 days
28871	JaafarTanoukhi author:JaafarTanoukhi	feat(Combinatorics/Digraph): Tournaments	Define orientations and tournaments. Related to #26771. Co-authored-by: Rida Hamadani --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-combinatorics new-contributor	62/0	Mathlib.lean,Mathlib/Combinatorics/Digraph/Orientation.lean,Mathlib/Combinatorics/Digraph/Tournament.lean	3	6	['JaafarTanoukhi', 'Rida-Hamadani', 'SnirBroshi', 'github-actions', 'mathlib4-merge-conflict-bot']	kmill assignee:kmill	105-49635 3 months ago	105-49636 3 months ago	86-45080 86 days
29526	llllvvuu author:llllvvuu	feat: `Multiset.map f` identifies `f` up to permutation	Motivation: Reason about `Fintype`-indexed families via `Multiset` equality. Example use case 1: ```lean theorem Matrix.IsHermitian.cfc_eigenvalues {d : Type} [Fintype d] [DecidableEq d] {M : Matrix d d 𝕜} (hM : M.IsHermitian) (f : ℝ → ℝ) (hcfc : Matrix.IsHermitian (cfc f M) := cfc_predicate f M) : ∃ (e : d ≃ d), hcfc.eigenvalues = f ∘ hM.eigenvalues ∘ e := by have := hcfc.roots_charpoly_eq_eigenvalues.symm rw [hM.charpoly_cfc_eq f, Polynomial.roots_prod] at this; swap · simp [Finset.prod_ne_zero_iff, Polynomial.X_sub_C_ne_zero] simp_rw [Polynomial.roots_X_sub_C, Multiset.bind_singleton] at this have he := (Multiset.compTriple_equivOfMapUnivEq this).comp_eq simp_rw [← Function.comp_def RCLike.ofReal, ← Function.comp_def f, Function.comp_assoc] at he exact ⟨_, RCLike.ofReal_injective.comp_left he.symm⟩ ``` Example use case 2 (on top of https://github.com/leanprover-community/mathlib4/pull/29610): ```lean theorem LinearMap.Eigenbasis.μ_equiv {ι ι' R G : Type} [Fintype ι] [Fintype ι'] [CommRing R] [IsDomain R] [AddCommGroup G] [Module R G] [Module.Free R G] [Module.Finite R G] {f : Module.End R G} (B₁ : f.Eigenbasis ι) (B₂ : f.Eigenbasis ι') : ∃ e : ι ≃ ι', B₁.μ = B₂.μ ∘ e := by classical have := congr(Polynomial.roots $(B₁.charpoly_eq.symm.trans B₂.charpoly_eq)) rw [Polynomial.roots_prod, Polynomial.roots_prod] at this; rotate_left · simp [Finset.prod_ne_zero_iff, Polynomial.X_sub_C_ne_zero] · simp [Finset.prod_ne_zero_iff, Polynomial.X_sub_C_ne_zero] simp_rw [Polynomial.roots_X_sub_C, Multiset.bind_singleton] at this exact ⟨Multiset.equivOfMapUnivEq this, (Multiset.compTriple_equivOfMapUnivEq this).comp_eq.symm⟩ ``` Co-authored-by: Aristotle Harmonic --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-data	35/0	Mathlib/Data/Multiset/Fintype.lean	1	9	['Ruben-VandeVelde', 'github-actions', 'llllvvuu', 'mathlib4-merge-conflict-bot', 'vihdzp', 'wwylele']	pechersky assignee:pechersky	105-49597 3 months ago	105-49598 3 months ago	69-23592 69 days
29947	JaafarTanoukhi author:JaafarTanoukhi	feat(Combinatorics/Digraph): Maps	Ported `SimpleGraph/Maps.lean` to `Digraph/Maps.lean` for future PRs related to issue #[26771](https://github.com/leanprover-community/mathlib4/issues/26771) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-combinatorics new-contributor	476/0	Mathlib.lean,Mathlib/Combinatorics/Digraph/Maps.lean	2	2	['github-actions', 'mathlib4-merge-conflict-bot']	awainverse assignee:awainverse	105-49001 3 months ago	105-49002 3 months ago	55-55764 55 days
31356	adomani author:adomani	feat: add inspect-like functions	Produces a tree-like formatting for `Syntax`, `Expr` and `InfoTree`. Especially for the `InfoTree`s, there are many parts of it that do not get printed. For instance, this is how the `InfoTree`s of `set_option linter.missingDocs true` get printed: ```lean inspectIT set_option linter.missingDocs true /- commandCtx \|-Info.ofCommandInfo: Lean.Elab.Command.elabSetOption, 'set_option…gDocs true' \| \|-Info.ofCompletionInfo.CompletionInfo.option 'set_option…issingDocs' \| \|-Info.ofOptionInfo: linter.missingDocs, Linter.linter.missingDocs -/ ``` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-meta	720/0	Mathlib.lean,Mathlib/Util/Inspect.lean,MathlibTest/Inspect.lean	3	3	['github-actions', 'mathlib4-merge-conflict-bot', 'plp127']	kim-em assignee:kim-em	105-44022 3 months ago	105-44023 3 months ago	11-75498 11 days
6993	jjaassoonn author:jjaassoonn	feat: lemmas about `AddMonoidAlgebra.{divOf, modOf}`	--- - [x] depends on: #7582 - [x] depends on: #8975 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	147/3	Mathlib/Algebra/MonoidAlgebra/Division.lean,Mathlib/Data/Finsupp/Basic.lean,Mathlib/Data/MvPolynomial/Basic.lean,Mathlib/Data/MvPolynomial/CommRing.lean,Mathlib/Data/MvPolynomial/Division.lean	5	42	['YaelDillies', 'alreadydone', 'digama0', 'eric-wieser', 'github-actions', 'jjaassoonn', 'leanprover-community-mathlib4-bot']	nobody	105-22946 3 months ago	603-29497 1 year ago	0-0 0 seconds
9339	FMLJohn author:FMLJohn	feat(RingTheory/GradedAlgebra/HomogeneousIdeal): given a finitely generated homogeneous ideal of a graded semiring, construct a finite spanning set for the ideal which only contains homogeneous elements	--- - [ ] depends on: #8187 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-ring-theory	402/4	Mathlib.lean,Mathlib/Algebra/DirectSum/Internal.lean,Mathlib/Algebra/GradedMonoid.lean,Mathlib/Algebra/Module/GradeZeroModule.lean,Mathlib/RingTheory/Finiteness.lean,Mathlib/RingTheory/GradedAlgebra/Basic.lean,Mathlib/RingTheory/GradedAlgebra/HomogeneousIdeal.lean,Mathlib/RingTheory/GradedAlgebra/Noetherian.lean	8	11	['FMLJohn', 'github-actions', 'jjaassoonn', 'leanprover-community-mathlib4-bot']	nobody	105-22899 3 months ago	211-43325 6 months ago	0-0 0 seconds
26890	robin-carlier author:robin-carlier	feat(CategoryTheory/Monoidal/DayConvolution): more API for `DayFunctor`	We provide some lemmas that helps characterizing the monoidal structure on `DayFunctor`, they are special cases of the lemmas for `LawfulDayConvolutionMonoidalCategoryStruct`. --- - [x] depends on: #26824 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-category-theory	1372/19	Mathlib.lean,Mathlib/CategoryTheory/Functor/KanExtension/Basic.lean,Mathlib/CategoryTheory/Monoidal/DayConvolution.lean,Mathlib/CategoryTheory/Monoidal/DayConvolution/DayFunctor.lean	4	n/a	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	105-22249 3 months ago	unknown	unknown
24016	plp127 author:plp127	feat: fine uniformity	Adds the fine uniformity, and proves some properties. --- - [ ] depends on: #24096 for showing the induced topology is equal on completely regular spaces [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology	283/0	Mathlib.lean,Mathlib/Topology/UniformSpace/FineUniformity.lean,Mathlib/Topology/UniformSpace/Uniformizable.lean	3	3	['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	99-69016 3 months ago	99-69017 3 months ago	0-0 0 seconds
26912	pechersky author:pechersky	chore(Algebra/Ring/Subring): simp tag `Subring.smul_def`	s-multiplying by a subtype is easiest to manipulate when both terms are in the ambient type. Many places that had to use the _def lemma for a rewrite, or to include it in a simp set, no longer have to. Ported from #25308 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) I found this being not-simp frustrating when talking about submodules over a valuation subring.	merge-conflict t-algebra label:t-algebra$	67/66	Mathlib/Algebra/Algebra/Subalgebra/Basic.lean,Mathlib/Algebra/Field/Subfield/Basic.lean,Mathlib/Algebra/Group/Subgroup/Actions.lean,Mathlib/Algebra/Group/Submonoid/MulAction.lean,Mathlib/Algebra/Module/LocalizedModule/Basic.lean,Mathlib/Algebra/Module/LocalizedModule/Exact.lean,Mathlib/Algebra/Module/LocalizedModule/IsLocalization.lean,Mathlib/Algebra/Module/LocalizedModule/Submodule.lean,Mathlib/Algebra/Ring/Periodic.lean,Mathlib/Algebra/Ring/Subring/Basic.lean,Mathlib/Algebra/Ring/Subsemiring/Basic.lean,Mathlib/Analysis/CStarAlgebra/Basic.lean,Mathlib/FieldTheory/KummerExtension.lean,Mathlib/GroupTheory/GroupAction/Defs.lean,Mathlib/GroupTheory/GroupAction/MultiplePrimitivity.lean,Mathlib/GroupTheory/GroupAction/MultipleTransitivity.lean,Mathlib/GroupTheory/GroupAction/SubMulAction/OfFixingSubgroup.lean,Mathlib/GroupTheory/GroupAction/SubMulAction/OfStabilizer.lean,Mathlib/LinearAlgebra/RootSystem/Irreducible.lean,Mathlib/LinearAlgebra/RootSystem/WeylGroup.lean,Mathlib/RingTheory/Etale/Kaehler.lean,Mathlib/RingTheory/Ideal/Over.lean,Mathlib/RingTheory/LocalProperties/Projective.lean,Mathlib/RingTheory/Localization/InvSubmonoid.lean,Mathlib/RingTheory/OreLocalization/Basic.lean	25	26	['artie2000', 'eric-wieser', 'github-actions', 'j-loreaux', 'kckennylau', 'leanprover-bot', 'leanprover-radar', 'linesthatinterlace', 'mathlib4-merge-conflict-bot', 'pechersky']	joelriou assignee:joelriou	78-81800 2 months ago	100-31349 3 months ago	64-44898 64 days
33561	kbuzzard author:kbuzzard	chore: cont -> continuous_toFun	This field is sometimes called `cont` and sometimes `continuous_toFun`. I noticed that the `continuity` tactic sometimes takes a lot longer to prove `cont` even if `continuous_toFun` is available so I thought I'd change them all to see if this speed up mathlib. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict	171/149	Mathlib/Algebra/Category/ContinuousCohomology/Basic.lean,Mathlib/Algebra/Category/ModuleCat/Topology/Homology.lean,Mathlib/Analysis/Analytic/Composition.lean,Mathlib/Analysis/Analytic/Polynomial.lean,Mathlib/Analysis/CStarAlgebra/CStarMatrix.lean,Mathlib/Analysis/CStarAlgebra/ContinuousFunctionalCalculus/NonUnital.lean,Mathlib/Analysis/CStarAlgebra/ContinuousFunctionalCalculus/Unital.lean,Mathlib/Analysis/Calculus/ContDiff/FaaDiBruno.lean,Mathlib/Analysis/Calculus/FDeriv/Basic.lean,Mathlib/Analysis/Calculus/FDeriv/Extend.lean,Mathlib/Analysis/Distribution/ContDiffMapSupportedIn.lean,Mathlib/Analysis/Distribution/DerivNotation.lean,Mathlib/Analysis/Distribution/SchwartzSpace.lean,Mathlib/Analysis/Distribution/TemperedDistribution.lean,Mathlib/Analysis/Distribution/TestFunction.lean,Mathlib/Analysis/Fourier/FourierTransform.lean,Mathlib/Analysis/Fourier/LpSpace.lean,Mathlib/Analysis/InnerProductSpace/LinearPMap.lean,Mathlib/Analysis/LocallyConvex/Barrelled.lean,Mathlib/Analysis/LocallyConvex/PointwiseConvergence.lean,Mathlib/Analysis/LocallyConvex/Separation.lean,Mathlib/Analysis/LocallyConvex/WeakOperatorTopology.lean,Mathlib/Analysis/LocallyConvex/WeakSpace.lean,Mathlib/Analysis/Normed/Affine/Isometry.lean,Mathlib/Analysis/Normed/Algebra/Spectrum.lean,Mathlib/Analysis/Normed/Lp/PiLp.lean,Mathlib/Analysis/Normed/Lp/ProdLp.lean,Mathlib/Analysis/Normed/Lp/lpSpace.lean,Mathlib/Analysis/Normed/Module/Alternating/Basic.lean,Mathlib/Analysis/Normed/Module/Multilinear/Basic.lean,Mathlib/Analysis/Normed/Module/WeakDual.lean,Mathlib/Analysis/Normed/Operator/Banach.lean,Mathlib/Analysis/Normed/Operator/BoundedLinearMaps.lean,Mathlib/Analysis/Normed/Operator/Extend.lean,Mathlib/Analysis/RCLike/Extend.lean,Mathlib/Geometry/Euclidean/Incenter.lean,Mathlib/Geometry/Manifold/LocalDiffeomorph.lean,Mathlib/Geometry/Manifold/MFDeriv/Atlas.lean,Mathlib/MeasureTheory/Function/ConditionalExpectation/Basic.lean,Mathlib/MeasureTheory/Function/ConditionalExpectation/CondexpL1.lean,Mathlib/MeasureTheory/Function/SimpleFuncDenseLp.lean,Mathlib/MeasureTheory/Integral/Bochner/L1.lean,Mathlib/MeasureTheory/Measure/FiniteMeasure.lean,Mathlib/NumberTheory/ModularForms/JacobiTheta/TwoVariable.lean,Mathlib/Probability/Distributions/Fernique.lean,Mathlib/Probability/Moments/CovarianceBilinDual.lean,Mathlib/Topology/Algebra/AffineSubspace.lean,Mathlib/Topology/Algebra/Algebra.lean,Mathlib/Topology/Algebra/ContinuousAffineEquiv.lean,Mathlib/Topology/Algebra/ContinuousAffineMap.lean,Mathlib/Topology/Algebra/Module/Alternating/Basic.lean,Mathlib/Topology/Algebra/Module/Alternating/Topology.lean,Mathlib/Topology/Algebra/Module/CharacterSpace.lean,Mathlib/Topology/Algebra/Module/Equiv.lean,Mathlib/Topology/Algebra/Module/LinearMap.lean,Mathlib/Topology/Algebra/Module/LinearMapPiProd.lean,Mathlib/Topology/Algebra/Module/Multilinear/Basic.lean,Mathlib/Topology/Algebra/Module/Multilinear/Topology.lean,Mathlib/Topology/Algebra/Module/PointwiseConvergence.lean,Mathlib/Topology/Algebra/Module/Star.lean,Mathlib/Topology/Algebra/Module/StrongTopology.lean,Mathlib/Topology/Algebra/Module/WeakDual.lean,Mathlib/Topology/ContinuousMap/Algebra.lean,Mathlib/Topology/ContinuousMap/Ideals.lean,Mathlib/Topology/Instances/TrivSqZeroExt.lean,Mathlib/Topology/VectorBundle/Basic.lean	66	5	['eric-wieser', 'github-actions', 'kbuzzard', 'leanprover-radar', 'mathlib4-merge-conflict-bot']	nobody	55-83875 1 month ago	55-83876 1 month ago	2-81715 2 days
33330	michael-novak-math author:michael-novak-math	feat: add arc-length reparametrization of parametrized curves	add new definitions of arc-length reparametrization and its corresponding parameter transformation and a theorem establishing the desired properties.	merge-conflict t-analysis new-contributor	311/0	Mathlib.lean,Mathlib/Analysis/Calculus/ArcLengthReparametrization.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/FundThmCalculus.lean,docs/references.bib,lake-manifest.json	5	53	['SnirBroshi', 'github-actions', 'grunweg', 'j-loreaux', 'mathlib4-merge-conflict-bot', 'michael-novak-math']	j-loreaux assignee:j-loreaux	55-73735 1 month ago	55-73736 1 month ago	6-81888 6 days
28700	Timeroot author:Timeroot	feat(ModelTheory): Set.Definable is transitive	--- This PR continues the work from #19695. Original PR: https://github.com/leanprover-community/mathlib4/pull/19695 - [ ] depends on: #26332 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-logic large-import	529/8	Mathlib/Data/Rel.lean,Mathlib/ModelTheory/Definability.lean,Mathlib/ModelTheory/Semantics.lean,Mathlib/ModelTheory/Syntax.lean,scripts/noshake.json	5	8	['Timeroot', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'staroperator']	nobody	55-24721 1 month ago	55-24723 1 month ago	3-12935 3 days
33435	astrainfinita author:astrainfinita	feat: algebra automorphisms of monoid algebras	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	53/3	Mathlib/Algebra/MonoidAlgebra/Basic.lean	1	2	['github-actions', 'mathlib4-merge-conflict-bot']	kbuzzard assignee:kbuzzard	50-7388 1 month ago	50-7389 1 month ago	13-17008 13 days
33126	CoolRmal author:CoolRmal	feat: function composition preserves boundedness	This PR adds the following theorem: if the range of a function `g` is bounded above, then `g ∘ f` is bounded above for all functions `f`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-order	12/0	Mathlib/Order/Bounds/Basic.lean	1	2	['github-actions', 'mathlib4-merge-conflict-bot']	bryangingechen assignee:bryangingechen	47-26252 1 month ago	47-26253 1 month ago	27-6197 27 days
20719	gio256 author:gio256	feat(AlgebraicTopology): delaborators for truncated simplicial notations	We add delaborators for the following notations, introduced in #20688: - `⦋m⦌ₙ`, which denotes the `m`-dimensional simplex in the `n`-truncated simplex category. - `X _⦋m⦌ₙ`, which denotes the `m`-th term of an `n`-truncated simplicial object `X`. - `X ^⦋m⦌ₙ`, which denotes the `m`-th term of an `n`-truncated cosimplicial object `X`. If `pp.proofs` is set to `true`, we also pretty-print the proof `p : m ≤ n` for all three notations as `⦋m, p⦌ₙ`, `X _⦋m, p⦌ₙ`, and `X ^⦋m, p⦌ₙ`, respectively. Credit to @kmill for one piece of code and much metaprogramming inspiration. --- - [x] depends on: #20688 - [x] depends on: #23018 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-meta infinity-cosmos t-algebraic-topology	525/33	Mathlib.lean,Mathlib/AlgebraicTopology/SimplexCategory/Basic.lean,Mathlib/AlgebraicTopology/SimplexCategory/Defs.lean,Mathlib/AlgebraicTopology/SimplicialObject/Basic.lean,Mathlib/Tactic.lean,Mathlib/Tactic/SimplexCategory.lean,Mathlib/Util/Superscript.lean,MathlibTest/SimplexCategory.lean,MathlibTest/SimplicialObject.lean,MathlibTest/superscript.lean,scripts/noshake.json	11	23	['eric-wieser', 'gio256', 'github-actions', 'joneugster', 'kim-em', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot']	joneugster assignee:joneugster	47-26039 1 month ago	216-35025 7 months ago	0-0 0 seconds
29587	uniwuni author:uniwuni	feat(GroupTheory/Finiteness): define finitely generated semigroups	We define finitely generated semigroups and basics similarly to monoids and groups and prove that semigroups and monoids remain finitely generated when a congruence is quotiented out. This will be important when further developing semigroup theory. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-group-theory	259/14	Mathlib/Algebra/Group/Submonoid/Defs.lean,Mathlib/GroupTheory/Finiteness.lean	2	4	['github-actions', 'mathlib4-merge-conflict-bot', 'plp127', 'uniwuni']	dupuisf assignee:dupuisf	45-37821 1 month ago	45-37821 1 month ago	25-78230 25 days
32546	anishrajeev author:anishrajeev	feat(ModelTheory): Prove compactness of the type space	Define the space of types and prove various topological properties of it (zero dimensional, totally separated, compact, baire). The goal is to formalize the proof of the Omitting Types Theorem - [ ] depends on: #32215	merge-conflict t-logic new-contributor	127/1	Mathlib.lean,Mathlib/ModelTheory/Topology/Types.lean,Mathlib/ModelTheory/Types.lean,Mathlib/Tactic/Linter/DirectoryDependency.lean	4	6	['NoneMore', 'anishrajeev', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	fpvandoorn assignee:fpvandoorn	43-17200 1 month ago	43-17203 1 month ago	3-84208 3 days
29014	ShreckYe author:ShreckYe	feat(Data/List/Scan): some theorems that relate `scanl` with `foldl`	I am not sure which is the best form of `getElem_scanl_eq_foldl_take` here, so I added several alternative forms. Feel free to remove any of them if necessary.	merge-conflict t-data	35/0	Mathlib/Data/List/Scan.lean	1	15	['ShreckYe', 'github-actions', 'mathlib4-merge-conflict-bot', 'themathqueen', 'vlad902']	pechersky assignee:pechersky	41-17045 1 month ago	114-68490 3 months ago	74-62841 74 days
16074	Rida-Hamadani author:Rida-Hamadani	feat: combinatorial maps and planar graphs	We define combinatorial maps, then we define planar graph using combinatorial maps. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-combinatorics	243/0	Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Planar.lean,Mathlib/Data/CombinatorialMap.lean	3	29	['MrBrain295', 'Parcly-Taxel', 'Rida-Hamadani', 'github-actions', 'lambda-fairy', 'leanprover-community-bot-assistant']	kmill assignee:kmill	32-66020 1 month ago	242-64244 7 months ago	0-0 0 seconds
34188	vihdzp author:vihdzp	feat: abbrev for `Std.Total (· ≤ ·)`	Apart from saving keystrokes, this ensures that the totality condition gets dualized by `to_dual` to itself, rather than to the equivalent and less idiomatic `Std.Total (· ≥ ·)`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-order	67/58	Mathlib/Algebra/Order/Archimedean/Class.lean,Mathlib/Algebra/Order/GroupWithZero/Canonical.lean,Mathlib/Algebra/Order/Ring/Canonical.lean,Mathlib/Data/Char.lean,Mathlib/Data/DFinsupp/Lex.lean,Mathlib/Data/Ordmap/Invariants.lean,Mathlib/Data/Ordmap/Ordset.lean,Mathlib/Data/Real/Basic.lean,Mathlib/Order/Antisymmetrization.lean,Mathlib/Order/Compare.lean,Mathlib/Order/Defs/LinearOrder.lean,Mathlib/Order/Filter/FilterProduct.lean,Mathlib/Order/Lattice.lean,Mathlib/Order/PropInstances.lean,Mathlib/Order/Quotient.lean,Mathlib/Order/RelClasses.lean,Mathlib/Order/Shrink.lean,Mathlib/Order/UpperLower/CompleteLattice.lean,Mathlib/Order/WithBot.lean,Mathlib/RingTheory/Valuation/ValuationRing.lean,Mathlib/RingTheory/Valuation/ValuationSubring.lean	21	8	['JovanGerb', 'github-actions', 'leanprover-radar', 'mathlib-merge-conflicts', 'plp127', 'vihdzp']	Vierkantor assignee:Vierkantor	29-8000 1 month ago	29-8001 1 month ago	13-55958 13 days
9820	jjaassoonn author:jjaassoonn	feat(RingTheory/GradedAlgebra/HomogeneousIdeal): generalize to homogeneous submodule	The definitions, constructions and theorems in `HomogeneousIdeal.lean` are generalized to a homogeneous submodules. So say $R$ is a ring and $M \cong \bigoplus_{i} M_i$ is an $R$-module. Then a homogeneous $R$-submodule of $M$ is an $R$-submodule $N$ such that for all $i$ and $n \in N$, $n_i \in N$. Note that this notion doesn't actually require $R$ to be graded and $M$ is a graded module. But for more interesting lemmas, we do need that $M$ is graded $R$-module. We bake the fact $R$ is graded into the definition of homogeneous submodule, otherwise, `CompleteLattice HomogeneousSubmodule` cannot find the order of synthesis (the proof depends on that $R$ is graded) All definitions/constructions/theorems have a copy for ideals as well, this is to make sure dot notation still works. The motivation of this generalization is graded quotient module --- - [x] depends on:#18728 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-ring-theory	516/185	Mathlib/Algebra/Module/GradedModule.lean,Mathlib/AlgebraicGeometry/ProjectiveSpectrum/Scheme.lean,Mathlib/AlgebraicGeometry/ProjectiveSpectrum/Topology.lean,Mathlib/RingTheory/GradedAlgebra/Homogeneous/Ideal.lean,Mathlib/RingTheory/GradedAlgebra/Homogeneous/Submodule.lean,Mathlib/RingTheory/GradedAlgebra/Radical.lean,scripts/nolints_prime_decls.txt	7	3	['github-actions', 'leanprover-community-bot-assistant']	nobody	23-43474 23 days ago	211-43332 6 months ago	0-0 0 seconds
34931	eric-wieser author:eric-wieser	perf: make TensorProduct.lift irreducible with a unification hint	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra label:t-algebra$	6/2	Mathlib/LinearAlgebra/TensorProduct/Basic.lean	1	7	['eric-wieser', 'github-actions', 'leanprover-radar', 'mathlib-merge-conflicts']	erdOne assignee:erdOne	20-11494 20 days ago	20-11495 20 days ago	0-0 0 seconds
33020	FormulaRabbit81 author:FormulaRabbit81	chore(Topology): Deprecate file	--- - [x] depends on: #30851 deprecation [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology large-import	82/49	Mathlib/Topology/Compactness/HilbertCubeEmbedding.lean,Mathlib/Topology/MetricSpace/HausdorffAlexandroff.lean,Mathlib/Topology/MetricSpace/PiNat.lean	3	3	['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	17-74505 17 days ago	76-61894 2 months ago	0-14835 4 hours
33281	michelsol author:michelsol	feat(Analysis/SpecialFunctions/Integrals): integral of 1/sqrt(1-x^2) and its integrability.	Add the integral of the derivative of arcsin and its integrability. --- - [ ] depends on: #33280 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-analysis new-contributor	59/0	Mathlib/Analysis/SpecialFunctions/Integrability/Basic.lean,Mathlib/Analysis/SpecialFunctions/Integrals/Basic.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/FundThmCalculus.lean	3	3	['github-actions', 'mathlib-dependent-issues', 'mathlib4-merge-conflict-bot']	nobody	17-43299 17 days ago	17-43301 17 days ago	0-2872 47 minutes
29281	plp127 author:plp127	doc: `Fin.natAdd_castLEEmb`	Change the docstring of `Fin.natAdd_castLEEmb` which confused me when I read it so I rewrote it. PS. this doesn't really follow the naming convention since data should be in `camelCase` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-data	2/3	Mathlib/Data/Fin/Embedding.lean	1	3	['github-actions', 'mathlib4-merge-conflict-bot', 'urkud']	nobody	17-23490 17 days ago	164-31958 5 months ago	18-38918 18 days
34156	zcyemi author:zcyemi	feat(Analysis/Convex/Between): add lemmas on convex combination of mem simplex interior	--- I add three lemmas of convex combinations preserving membership in the interior of a simplex. And also open a zulip thread [#mathlib4 > Best place for convex combination and simplex interior](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Best.20place.20for.20convex.20combination.20and.20simplex.20interior/with/568558406) deps: - [ ] depends on: #33852	merge-conflict t-analysis	170/0	Mathlib/Analysis/Convex/Between.lean,Mathlib/LinearAlgebra/AffineSpace/Independent.lean	2	3	['github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts']	nobody	17-19216 17 days ago	17-19216 17 days ago	0-3761 1 hour
16215	adomasbaliuka author:adomasbaliuka	feat(Tactic/Linter): lint unwanted unicode	Add a text-based style linter that checks all unicode characters. - Only allow whitelisted characters, with a suggestion to add the flagged character to the whitelist - Some characters are specified to use emoji-variant or text-variant. The linter ensures these variant-selectors only appear in the correct places and provides an auto-fix to clean them up. --- Discussed at [Zulip](https://leanprover.zulipchat.com/#narrow/stream/287929-mathlib4/topic/Whitelist.20for.20Unicode.3F/near/448721083) The current proposal checks each character against a whitelist. There is also the question of what the whitelist should contain. A reasonable whitelist might be "all unicode currently in Mathlib" ∪ [Wikipedia/Mathematical_operators_and_symbols_in_Unicode](https://en.wikipedia.org/wiki/Mathematical_operators_and_symbols_in_Unicode) ∪ [EdAyers/mathlib3/docs/unicode.md](https://github.com/EdAyers/mathlib/blob/fb5c2ffe917049959597b0a93b872e91f4004922/docs/unicode.md). Currently implemented is a subset of this list closer to what's currently present in mathlib. - [x] depends on: #17068 - [x] depends on: #17116 - [x] depends on: #17129 (part 1 of this PR) - ~depends on #34719 (part 1 of this PR)~ - ~depends on: #17131 (part 2 of this PR)~ (obsolete) - [x] depends on: #34022 (part 2 of this PR) - Future note: @adomasbaliuka says: "we might add something to the Mathlib 4 docs about this as well?" [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-linter	462/15	Mathlib/GroupTheory/GroupExtension/Defs.lean,Mathlib/Tactic/Linter/TextBased.lean,Mathlib/Tactic/Linter/UnicodeLinter.lean,Mathlib/Tactic/Widget/Calc.lean,Mathlib/Tactic/Widget/CongrM.lean,Mathlib/Tactic/Widget/Conv.lean,Mathlib/Tactic/Widget/GCongr.lean,Mathlib/Topology/ContinuousFunction/Weierstrass.lean,test/LintStyle.lean	9	51	['adomasbaliuka', 'eric-wieser', 'github-actions', 'grunweg', 'joneugster', 'mathlib-dependent-issues']	joneugster assignee:joneugster	16-15731 16 days ago	16-15734 16 days ago	0-0 0 seconds
32918	michelsol author:michelsol	feat: define `supEdist` and `supDist`	Create a new file Topology.MetricSpace.SupDistance and define the supremal distance in (extended) metric spaces. The defined `supEdist` and `supDist` will have similar theory to the already existing `infEdist` and `infDist`. The motivation is to be able to define the radius of a minimal bounding sphere as the infimum of the supDist later. [zulip discussion here](https://leanprover.zulipchat.com/#narrow/channel/116395-maths/topic/Formalizing.20Jung's.20theorem.20and.20minimal.20bounding.20spheres)	merge-conflict t-topology new-contributor	75/0	Mathlib.lean,Mathlib/Topology/MetricSpace/SupDistance.lean	2	5	['github-actions', 'mathlib4-merge-conflict-bot', 'michelsol', 'urkud']	RemyDegenne assignee:RemyDegenne	16-13398 16 days ago	58-5783 1 month ago	21-5159 21 days
33288	vihdzp author:vihdzp	chore(Combinatorics/SimpleGraph/Paths): review API	This PR does the following: - Add `grind` annotations. - Rename theorems `X_isY` to the more idiomatic `isY_X`. - Remove many redundant namespaces. - Golf accordingly. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-combinatorics	154/122	Mathlib/Combinatorics/SimpleGraph/Acyclic.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/Connected.lean,Mathlib/Combinatorics/SimpleGraph/Matching.lean,Mathlib/Combinatorics/SimpleGraph/Metric.lean,Mathlib/Combinatorics/SimpleGraph/Paths.lean,Mathlib/Combinatorics/SimpleGraph/Walks/Maps.lean	6	3	['github-actions', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot']	b-mehta assignee:b-mehta	16-6667 16 days ago	16-6668 16 days ago	43-26072 43 days
25980	Multramate author:Multramate	refactor(Algebra/Group/Submonoid/Operations): rename restrict to domRestrict and add restrict	And update the documentation for consistency	merge-conflict t-group-theory	145/123	Mathlib/Algebra/Group/Subgroup/Basic.lean,Mathlib/Algebra/Group/Subgroup/Ker.lean,Mathlib/Algebra/Group/Submonoid/Operations.lean,Mathlib/GroupTheory/FiniteAbelian/Duality.lean,Mathlib/GroupTheory/MonoidLocalization/Basic.lean,Mathlib/GroupTheory/MonoidLocalization/Maps.lean,Mathlib/GroupTheory/MonoidLocalization/MonoidWithZero.lean,Mathlib/GroupTheory/PGroup.lean,Mathlib/GroupTheory/QuotientGroup/Basic.lean,Mathlib/GroupTheory/Transfer.lean,Mathlib/LinearAlgebra/RootSystem/WeylGroup.lean,Mathlib/NumberTheory/NumberField/CMField.lean,Mathlib/NumberTheory/NumberField/Ideal/Basic.lean,Mathlib/RingTheory/Localization/Defs.lean	14	10	['Multramate', 'copilot-pull-request-reviewer', 'github-actions', 'mathlib-merge-conflicts']	nobody	14-79744 14 days ago	14-79745 14 days ago	7-25720 7 days
25981	Multramate author:Multramate	feat(GroupTheory/GroupAction/Basic): define homomorphisms of fixed subgroups induced by homomorphisms of groups	This PR continues the work from #10126. Original PR: https://github.com/leanprover-community/mathlib4/pull/10126	merge-conflict large-import t-group-theory	218/144	Mathlib/Algebra/Group/Subgroup/Basic.lean,Mathlib/Algebra/Group/Subgroup/Ker.lean,Mathlib/Algebra/Group/Submonoid/Operations.lean,Mathlib/Algebra/Ring/Action/Submonoid.lean,Mathlib/GroupTheory/FiniteAbelian/Duality.lean,Mathlib/GroupTheory/GroupAction/Defs.lean,Mathlib/GroupTheory/MonoidLocalization/Basic.lean,Mathlib/GroupTheory/MonoidLocalization/Maps.lean,Mathlib/GroupTheory/MonoidLocalization/MonoidWithZero.lean,Mathlib/GroupTheory/PGroup.lean,Mathlib/GroupTheory/QuotientGroup/Basic.lean,Mathlib/GroupTheory/Transfer.lean,Mathlib/LinearAlgebra/RootSystem/WeylGroup.lean,Mathlib/NumberTheory/NumberField/CMField.lean,Mathlib/NumberTheory/NumberField/Ideal/Basic.lean,Mathlib/RingTheory/Localization/Defs.lean	16	8	['copilot-pull-request-reviewer', 'github-actions', 'mathlib-merge-conflicts']	nobody	14-79743 14 days ago	14-79743 14 days ago	4-79093 4 days
33795	alreadydone author:alreadydone	feat(Topology/Sheaves): LocalPredicate prerequisite for étalé spaces	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology	418/143	Mathlib/AlgebraicGeometry/ProjectiveSpectrum/StructureSheaf.lean,Mathlib/Geometry/Manifold/Sheaf/Smooth.lean,Mathlib/Logic/Equiv/Basic.lean,Mathlib/Topology/Sheaves/LocalPredicate.lean,Mathlib/Topology/Sheaves/Sheafify.lean,Mathlib/Topology/Sheaves/Stalks.lean	6	12	['adamtopaz', 'alreadydone', 'dagurtomas', 'github-actions', 'mathlib-merge-conflicts']	adamtopaz assignee:adamtopaz	14-57377 14 days ago	14-57378 14 days ago	34-21696 34 days
34674	Citronhat author:Citronhat	feat(Algebra/Order/Ring): replace ENNReal lemmas with WithTop versions	* Add `WithTop` versions of basic multiplicative order lemmas. * Use the new `WithTop` lemmas to replace `ENNReal` proofs and address six TODOs. * Fix a typo in the `pos_of_ne_zero` alias name.	merge-conflict t-algebra new-contributor label:t-algebra$	46/15	Mathlib/Algebra/Order/Monoid/Canonical/Defs.lean,Mathlib/Algebra/Order/Ring/WithTop.lean,Mathlib/Data/ENNReal/Operations.lean	3	5	['Citronhat', 'Ruben-VandeVelde', 'github-actions', 'mathlib-merge-conflicts']	Ruben-VandeVelde assignee:Ruben-VandeVelde	14-37247 14 days ago	14-37248 14 days ago	17-1225 17 days
33416	vihdzp author:vihdzp	chore(Order/GameAdd): add `elab_as_elim` attributes	This PR does three things: - Rename `GameAdd.fix` to the more illustrative `GameAdd.recursion` - Add `elab_as_elim` attributes on `GameAdd.recursion` - Deprecate the duplicate `GameAdd.induction` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-order	24/14	Mathlib/Order/GameAdd.lean,Mathlib/SetTheory/PGame/Order.lean,Mathlib/SetTheory/ZFC/Ordinal.lean	3	6	['github-actions', 'grunweg', 'mathlib-merge-conflicts', 'ocfnash', 'vihdzp']	alreadydone assignee:alreadydone	12-66570 12 days ago	12-66570 12 days ago	50-67636 50 days
33746	ster-oc author:ster-oc	feat(Algebra/Module/ZLattice): align `ZSpan.floor` to `Int.floor` API	This PR adds some of the existent lemmas about `Int.floor`, `Int.ceil` and `Int.fract` to the `ZSpan` namespace. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra new-contributor label:t-algebra$	353/145	Mathlib/Algebra/Module/ZLattice/Basic.lean,Mathlib/Algebra/Order/Floor/Ring.lean,Mathlib/Topology/Algebra/Order/Floor.lean	3	8	['github-actions', 'joelriou', 'mathlib-merge-conflicts', 'ster-oc']	joelriou assignee:joelriou	9-54145 9 days ago	9-54145 9 days ago	30-23357 30 days
35555	JovanGerb author:JovanGerb	perf: add `AddMonoid` shortcut instance for linear maps	The hierarchy of classes is such that `AddCommMonoid` is not a direct parent of `AddCommGroup`. This means that when unifying an instance that comes from `AddCommMonoid` with one that comes from `AddCommGroup`, we end up having to go through the shared parent `AddMonoid`. Hence, it can be beneficial to have a separately defined `AddMonoid` instance. It might be worth it to try to switch up the order of the parents of `AddCommGroup`/`CommGroup` in the `extends` clause, and see if that has beneficial effects. Though this will affect many things, and in particular won't interact well with the `backward.respectTransparency` mess that is going on at the moment. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict	23/7	Mathlib/Algebra/Module/LinearMap/Defs.lean,Mathlib/LinearAlgebra/Multilinear/Basic.lean,Mathlib/Topology/Algebra/Module/LinearMap.lean,Mathlib/Topology/Algebra/Module/Multilinear/Basic.lean	4	5	['JovanGerb', 'github-actions', 'leanprover-radar', 'mathlib-merge-conflicts']	robin-carlier assignee:robin-carlier	8-39266 8 days ago	8-39267 8 days ago	4-32369 4 days
34854	GrigorenkoPV author:GrigorenkoPV	chore(Combinatorics/Enumerative/Catalan): split into `Basic` & `Tree`	--- Split off from #34853 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor	228/195	Mathlib.lean,Mathlib/Combinatorics/Enumerative/Catalan.lean,Mathlib/Combinatorics/Enumerative/Catalan/Basic.lean,Mathlib/Combinatorics/Enumerative/Catalan/Tree.lean,Mathlib/Combinatorics/Enumerative/DyckWord.lean,Mathlib/RingTheory/PowerSeries/Catalan.lean	6	5	['SnirBroshi', 'github-actions', 'mathlib-merge-conflicts', 'vihdzp']	thorimur assignee:thorimur	7-81800 7 days ago	7-81801 7 days ago	19-76299 19 days
33791	PhoenixIra author:PhoenixIra	feat: Generalization of FixedPointApproximants to CompletePartialOrder	--- This PR provides a generalization of FixedPointApproximants to CompletePartialOrder. Not every theorem can be generalized, as sometimes we require additional conditions (namely `x ≤ f x`) in order to guarantee that the set is directed and thus the supremum is well-defined. This is not necessary in a CompleteLattice. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-order new-contributor	223/100	Mathlib/Order/CompletePartialOrder.lean,Mathlib/SetTheory/Ordinal/FixedPointApproximants.lean	2	21	['PhoenixIra', 'github-actions', 'mathlib-merge-conflicts', 'vihdzp']	PhoenixIra and vihdzp assignee:PhoenixIra assignee:vihdzp	5-4479 5 days ago	5-4479 5 days ago	49-24213 49 days
34952	joneugster author:joneugster	feat(scripts/autolabel): use `Cli` and integrate `curl` call into `autolabel`	- use `Cli` for `lake exe autolabel` - add arguments `--pr xxx --gh` and `--pr xxx --curl ` to chose between different interaction methods with github - add `--force` to skip the check whether labels are already present. (note: the current `curl` setup doesn't perform this step, so I left it as a `TODO` in this PR, too) - make CI-workflow simpler and more robust by removing current stdout-parsing of the debug-messages which `autolabel` emits. ### Testing Make some local changes and commit them. Ensure your local `origin/master` is in sync with `upstream/master` if you are on a fork. - `lake exe autolabel`: prints the labels which would be applicable - `lake exe autolabel --pr 34952 --gh --force` adds these labels to this PR using `gh`. - `lake exe autolabel --pr 34952 --gh` adds these labels to this PR using `gh` if no topic labels are present. - `lake exe autolabel --pr 34952 --curl ` adds these labels to this PR using `curl`. This requires a github access token for authentication --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict CI	85/72	.github/workflows/add_label_from_diff.yaml,scripts/autolabel.lean	2	3	['github-actions', 'mathlib-merge-conflicts']	nobody	4-4511 4 days ago	4-4512 4 days ago	14-62968 14 days
32033	Thmoas-Guan author:Thmoas-Guan	feat(Algebra): injective dimension equal supremum of localized module	In this PR, we proved that for module over Noetherian ring, projective dimension is equal to the supremum of injective dimension of localized modules over all prime/maximal ideals. --- - [ ] depends on: #31995 - [ ] depends on: #31998 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra large-import label:t-algebra$	363/9	Mathlib.lean,Mathlib/Algebra/Category/ModuleCat/Localization.lean,Mathlib/Algebra/Module/Equiv/Defs.lean,Mathlib/Algebra/Module/Injective.lean,Mathlib/RingTheory/LocalProperties/Injective.lean,Mathlib/RingTheory/LocalProperties/InjectiveDimension.lean	6	4	['github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot']	nobody	3-45860 3 days ago	3-45860 3 days ago	0-2505 41 minutes
26942	pechersky author:pechersky	feat(RingTheory/Valuation/ValueGroupIso): isomorphism of value groups when compatible	and also to the ValuativeRel's value group by request from comment in https://github.com/leanprover-community/mathlib4/pull/26754#issuecomment-3051770901 - [ ] depends on: #26588 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) - [x] depends on: #26939 - [x] depends on: #26940 - [x] depends on: #26941	blocked-by-other-PR merge-conflict t-order t-ring-theory	299/3	Mathlib.lean,Mathlib/Algebra/GroupWithZero/Range.lean,Mathlib/Algebra/Order/GroupWithZero/Range.lean,Mathlib/Algebra/Order/GroupWithZero/WithZero.lean,Mathlib/Algebra/Order/Monoid/WithTop.lean,Mathlib/RingTheory/Valuation/ValueGroupIso.lean	6	10	['faenuccio', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'pechersky']	faenuccio assignee:faenuccio	105-50089 3 months ago	105-50090 3 months ago	10-67838 10 days
25906	pfaffelh author:pfaffelh	feat(Topology/Compactness/CompactSystem): closed and compact square cylinders form a compact system	feat (Topology/Compactness/CompactSystem): Closed and compact square cylinders form a compact system. A square cylinder is a set of the form `s.pi t` in a product space. A closed compact square cylinder has `IsClosed (t i)` and `IsCompact (t i)` for all `i ∈ s`. This set system is a compact system (as introduced in PR #25899). Streamline the definition of square cylinders in MeasureTheory/Constructions/Cylinders on the way. Co-authors: Rémy Degenne remy.degenne@inria.fr --- - [ ] depends on: #25899 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) --- This PR continues the work from #24542. Original PR: https://github.com/leanprover-community/mathlib4/pull/24542	merge-conflict t-topology	716/65	Mathlib.lean,Mathlib/Data/Set/Accumulate.lean,Mathlib/Data/Set/Dissipate.lean,Mathlib/Data/Set/Prod.lean,Mathlib/MeasureTheory/Constructions/Cylinders.lean,Mathlib/MeasureTheory/Constructions/ProjectiveFamilyContent.lean,Mathlib/MeasureTheory/PiSystem.lean,Mathlib/Topology/Compactness/CompactSystem.lean	8	4	['github-actions', 'leanprover-community-bot-assistant', 'mathlib-dependent-issues', 'mathlib4-merge-conflict-bot']	nobody	1-77048 1 day ago	1-77050 1 day ago	0-383 6 minutes
35198	j-loreaux author:j-loreaux	feat: generalize Hölder's inequality for sums to `Real.HolderTriple`	Currently the API exists only for `Real.HolderConjugate`. This generalizes it in anticipation of #35197, which implements the Hölder framework for `lp` spaces. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-analysis	161/40	Mathlib/Analysis/MeanInequalities.lean,Mathlib/Data/Real/ConjExponents.lean	2	3	['github-actions', 'mathlib-merge-conflicts']	ADedecker assignee:ADedecker	1-59888 1 day ago	1-59889 1 day ago	16-29794 16 days
34711	urkud author:urkud	refactor(padicValNat): redefine using `maxPowDvdDiv`	- rename `maxPowDiv` to `maxPowDvdDiv`; - make it return `a / b ^ n` too; - optimize it to use `O(log (logb b a))` steps; - redefine `padicValNat` to be `maxPowDvdDiv .. \|>.1` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict	275/149	Mathlib/Data/Nat/MaxPowDiv.lean,Mathlib/NumberTheory/Padics/PadicNumbers.lean,Mathlib/NumberTheory/Padics/PadicVal/Basic.lean,Mathlib/NumberTheory/Padics/PadicVal/Defs.lean,Mathlib/NumberTheory/SumTwoSquares.lean	5	3	['b-mehta', 'github-actions', 'mathlib-merge-conflicts']	b-mehta and dagurtomas assignee:dagurtomas assignee:b-mehta	1-45536 1 day ago	1-59891 1 day ago	9-78412 9 days
31135	kckennylau author:kckennylau	feat(RingTheory): is localization iff is localization on saturation	In this PR we show that `A` is a localization of `R` on the submonoid `S` iff it is so on the saturation of `S`. Crucially, the saturation of `S` is precisely the elements that become a unit in `A`. --- - [ ] depends on: #31132 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-ring-theory	293/0	Mathlib.lean,Mathlib/Algebra/Group/Submonoid/Saturation.lean,Mathlib/RingTheory/Localization/Saturation.lean	3	5	['alreadydone', 'github-actions', 'mathlib-dependent-issues', 'mathlib4-merge-conflict-bot']	nobody	1-17535 1 day ago	1-17537 1 day ago	0-169 2 minutes
30365	kckennylau author:kckennylau	feat(RingTheory): define R-linear graded algebra homomorphism	This PR defines R-linear graded algebra homomorphisms, which are R-algebra homomorphisms that preserve the grading. We also provide the basic properties (aka the "API"). Zulip discussion: [#mathlib4 > redefine Graded Algebra](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/redefine.20Graded.20Algebra/near/543847326) --- Split from #26061. - [ ] depends on: #30355 - [ ] depends on: #30312 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-ring-theory	642/0	Mathlib.lean,Mathlib/Data/FunLike/GradedFunLike.lean,Mathlib/RingTheory/GradedAlgebra/AlgHom.lean,Mathlib/RingTheory/GradedAlgebra/RingHom.lean	4	3	['github-actions', 'mathlib-dependent-issues', 'mathlib4-merge-conflict-bot']	nobody	1-17501 1 day ago	1-17504 1 day ago	0-578 9 minutes
30334	kckennylau author:kckennylau	feat(RingTheory): define maps of homogeneous ideals	In this file we define `HomogeneousIdeal.map` and `HomogeneousIdeal.comap`, similar to and based on the existing `Ideal.map` and `Ideal.comap`. More concretely, a graded ring homomorphism `𝒜 →+*ᵍ ℬ` induces a "Galois connection" between the homogeneous ideals in `𝒜` and the homogeneous ideals in `ℬ`. --- Split from #26061. - [ ] depends on: #30312 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-ring-theory	441/0	Mathlib.lean,Mathlib/RingTheory/GradedAlgebra/Hom.lean,Mathlib/RingTheory/GradedAlgebra/Homogeneous/Ideal.lean,Mathlib/RingTheory/GradedAlgebra/Homogeneous/Maps.lean	4	3	['github-actions', 'mathlib-dependent-issues', 'mathlib4-merge-conflict-bot']	nobody	1-17496 1 day ago	1-17499 1 day ago	0-1744 29 minutes
35659	BryceT233 author:BryceT233	chore(Data/Finsupp): update pointwise module structure	This is the 3rd PR split from #34936 to make the review process easier. It updates the pointwise module structure `Module (ι → R) (ι →₀ M)` where `R` is a semiring and `M` is an `R`-module. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	new-contributor t-data	25/18	Mathlib/Data/Finsupp/Pointwise.lean	1	2	['github-actions']	joneugster assignee:joneugster	2-22931 2 days ago	9-84949 9 days ago	9-85001 9 days
35800	xroblot author:xroblot	feat(RamificationInertia): decomposition fields and inertia fields are unique (up to isomorphism)	--- - [ ] depends on: #35303 - [ ] depends on: #35797 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-number-theory	205/1	Mathlib.lean,Mathlib/Algebra/Algebra/Defs.lean,Mathlib/FieldTheory/Galois/IsGaloisGroup.lean,Mathlib/NumberTheory/RamificationInertia/HilbertTheory.lean,Mathlib/RingTheory/Ideal/Pointwise.lean	5	4	['github-actions', 'joneugster', 'mathlib-dependent-issues', 'mathlib-merge-conflicts']	nobody	4-17102 4 days ago	4-17102 4 days ago	0-1235 20 minutes
35429	CoolRmal author:CoolRmal	feat: a convex, lower-semicontinuous, and positively homogeneous function is the supremum of a family of linear functions	This PR adds more results related to the #31411. The motivation of this PR is explained over here: #35431. The main theorems proved in this PR are - `convexCone_sSup_linear_eq`: A function `φ : E → ℝ` that is convex, lower-semicontinuous, and positively homogeneous on a closed, convex, and pointed cone `c` is the supremum of a family of functions that are the restrictions to `s` of continuous linear forms in `E`. I actually prove this theorem under the assumption `∀ x ∈ c, ∀ᶠ μ in atTop, φ (μ • x) = μ * φ x`, which is weaker than positive homogeneity. - We then apply the theorem above to prove `univ_sSup_linear_eq`, which says that a function that is convex, lower-semicontinuous, and positively homogeneous on the entire space is the supremum of a family of continuous linear forms in `E`. - Similar to what I have done in #31411, I also proved the countable/sequential version of these theorems, under the assumption that the underlying space `E` is hereditarily Lindelof. --- - [ ] depends on #27953 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-analysis	351/24	Mathlib.lean,Mathlib/Analysis/Convex/Approximation.lean,Mathlib/MeasureTheory/Function/ConditionalExpectation/CondJensen.lean,Mathlib/MeasureTheory/MeasurableSpace/Constructions.lean	4	2	['github-actions', 'joneugster']	j-loreaux assignee:j-loreaux	0-74820 20 hours ago	4-80521 4 days ago	15-59988 15 days
36107	sgouezel author:sgouezel	chore: mark definitions outputting classes as `implicit_reducible`	Definitions outputting classes are here to be used as instances somewhere. If they are not implicit-reducible, then this use as instance is likely to encounter issues for defeq at instance reducibility. This PR marks all class returning definitions of the library as implicit_reducible, using the linter of #36031 and iteration of a python script with manual tweaking. Marking setoids as implicit_reducible creates a performance issue (why is setoid a class, by the way?) so I kept some of them unchanged. I'm not sure that it makes sense to mark all class returning defs as implicit_reducible (setoids are a counterexample, but Fintype is also probably not very sensible). On a side note, many many things in category theory are classes but have defs that construct them, so many many changes of the PR are in category theory. I have no opinion on whether this is desirable as I don't know the design decisions in this corner of the library. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)		755/93	Mathlib/Algebra/Algebra/ZMod.lean,Mathlib/Algebra/BrauerGroup/Defs.lean,Mathlib/Algebra/Category/FGModuleCat/Colimits.lean,Mathlib/Algebra/Category/FGModuleCat/Limits.lean,Mathlib/Algebra/Category/Grp/Abelian.lean,Mathlib/Algebra/Category/ModuleCat/Abelian.lean,Mathlib/Algebra/Category/ModuleCat/EpiMono.lean,Mathlib/Algebra/Category/ModuleCat/Presheaf/Sheafify.lean,Mathlib/Algebra/CharP/Invertible.lean,Mathlib/Algebra/CharP/MixedCharZero.lean,Mathlib/Algebra/DirectSum/Decomposition.lean,Mathlib/Algebra/Field/IsField.lean,Mathlib/Algebra/FreeMonoid/Basic.lean,Mathlib/Algebra/GCDMonoid/Basic.lean,Mathlib/Algebra/Homology/ComplexShapeSigns.lean,Mathlib/Algebra/Lie/Basic.lean,Mathlib/Algebra/Lie/Classical.lean,Mathlib/Algebra/Lie/Extension.lean,Mathlib/Algebra/Module/GradedModule.lean,Mathlib/Algebra/Module/NatInt.lean,Mathlib/Algebra/Module/Submodule/Defs.lean,Mathlib/Algebra/Module/Torsion/Basic.lean,Mathlib/Algebra/MonoidAlgebra/Module.lean,Mathlib/Algebra/Order/Archimedean/Basic.lean,Mathlib/Algebra/Order/Floor/Defs.lean,Mathlib/Algebra/Polynomial/Div.lean,Mathlib/Algebra/SkewMonoidAlgebra/Basic.lean,Mathlib/Algebra/Star/RingQuot.lean,Mathlib/AlgebraicGeometry/Cover/Directed.lean,Mathlib/AlgebraicTopology/ModelCategory/Basic.lean,Mathlib/Analysis/CStarAlgebra/CStarMatrix.lean,Mathlib/Analysis/CStarAlgebra/Matrix.lean,Mathlib/Analysis/CStarAlgebra/Module/Defs.lean,Mathlib/Analysis/Complex/UpperHalfPlane/Metric.lean,Mathlib/Analysis/Distribution/TestFunction.lean,Mathlib/Analysis/InnerProductSpace/Basic.lean,Mathlib/Analysis/InnerProductSpace/Defs.lean,Mathlib/Analysis/InnerProductSpace/OfNorm.lean,Mathlib/Analysis/LocallyConvex/WithSeminorms.lean,Mathlib/Analysis/Matrix/Order.lean,Mathlib/Analysis/Matrix/PosDef.lean,Mathlib/Analysis/Normed/Algebra/Exponential.lean,Mathlib/Analysis/Normed/Field/Basic.lean,Mathlib/Analysis/Normed/Group/AddTorsor.lean,Mathlib/Analysis/Normed/Module/Basic.lean,Mathlib/Analysis/Normed/Ring/Basic.lean,Mathlib/Analysis/Normed/Unbundled/SpectralNorm.lean,Mathlib/Analysis/RCLike/Basic.lean,Mathlib/CategoryTheory/Abelian/Basic.lean,Mathlib/CategoryTheory/Abelian/NonPreadditive.lean,Mathlib/CategoryTheory/Abelian/Transfer.lean,Mathlib/CategoryTheory/Bicategory/Monad/Basic.lean,Mathlib/CategoryTheory/CatCommSq.lean,Mathlib/CategoryTheory/Center/Linear.lean,Mathlib/CategoryTheory/ConcreteCategory/Forget.lean,Mathlib/CategoryTheory/Enriched/Basic.lean,Mathlib/CategoryTheory/Enriched/FunctorCategory.lean,Mathlib/CategoryTheory/Enriched/Ordinary/Basic.lean,Mathlib/CategoryTheory/EpiMono.lean,Mathlib/CategoryTheory/FiberedCategory/HasFibers.lean,Mathlib/CategoryTheory/Functor/Functorial.lean,Mathlib/CategoryTheory/Groupoid.lean,Mathlib/CategoryTheory/Groupoid/Subgroupoid.lean,Mathlib/CategoryTheory/IsConnected.lean,Mathlib/CategoryTheory/Limits/Constructions/LimitsOfProductsAndEqualizers.lean,Mathlib/CategoryTheory/Limits/Creates.lean,Mathlib/CategoryTheory/Limits/Final.lean,Mathlib/CategoryTheory/Limits/FullSubcategory.lean,Mathlib/CategoryTheory/Limits/MorphismProperty.lean,Mathlib/CategoryTheory/Limits/Preorder.lean,Mathlib/CategoryTheory/Limits/Preserves/Creates/Finite.lean,Mathlib/CategoryTheory/Limits/Shapes/ConcreteCategory.lean,Mathlib/CategoryTheory/Limits/Shapes/NormalMono/Basic.lean,Mathlib/CategoryTheory/Limits/Shapes/ZeroMorphisms.lean,Mathlib/CategoryTheory/Localization/Bifunctor.lean,Mathlib/CategoryTheory/Localization/CalculusOfFractions/Preadditive.lean,Mathlib/CategoryTheory/Localization/HasLocalization.lean,Mathlib/CategoryTheory/Localization/Linear.lean,Mathlib/CategoryTheory/Localization/LocallySmall.lean,Mathlib/CategoryTheory/Localization/Monoidal/Functor.lean,Mathlib/CategoryTheory/Localization/Predicate.lean,Mathlib/CategoryTheory/Localization/Triangulated.lean,Mathlib/CategoryTheory/Localization/Trifunctor.lean,Mathlib/CategoryTheory/LocallyCartesianClosed/ChosenPullbacksAlong.lean,Mathlib/CategoryTheory/LocallyCartesianClosed/ExponentiableMorphism.lean,Mathlib/CategoryTheory/Monad/Comonadicity.lean,Mathlib/CategoryTheory/Monad/Limits.lean,Mathlib/CategoryTheory/Monad/Monadicity.lean,Mathlib/CategoryTheory/Monoidal/Action/End.lean,Mathlib/CategoryTheory/Monoidal/Action/Opposites.lean,Mathlib/CategoryTheory/Monoidal/Bimod.lean,Mathlib/CategoryTheory/Monoidal/Braided/Basic.lean,Mathlib/CategoryTheory/Monoidal/Braided/Multifunctor.lean,Mathlib/CategoryTheory/Monoidal/Braided/Reflection.lean,Mathlib/CategoryTheory/Monoidal/Cartesian/Basic.lean,Mathlib/CategoryTheory/Monoidal/Cartesian/CommGrp_.lean,Mathlib/CategoryTheory/Monoidal/Cartesian/Grp_.lean,Mathlib/CategoryTheory/Monoidal/Cartesian/Mon_.lean,Mathlib/CategoryTheory/Monoidal/Closed/Basic.lean,Mathlib/CategoryTheory/Monoidal/Closed/Cartesian.lean	337	3	['github-actions', 'leanprover-radar', 'sgouezel']	nobody	0-42068 11 hours ago	0-47893 13 hours ago	0-47868 13 hours
36118	jjdishere author:jjdishere	fix(NumberTheory/Padics): remove diamond normed instance on C_p	In this PR, we refactor the normed instance on $\mathbb{C}_p$ to the norm extended along completion, and show that this is compatible with valuation. Also added NontriviallyNormedField and CharZero instances. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) - [ ] depends on: #26390		73/28	Mathlib/Analysis/Normed/Unbundled/SpectralNorm.lean,Mathlib/NumberTheory/Padics/Complex.lean	2	11	['github-actions', 'jjdishere', 'riccardobrasca']	riccardobrasca assignee:riccardobrasca	0-24027 6 hours ago	0-40146 11 hours ago	0-40121 11 hours

Stale new contributor PRs

Number	Author	Title	Description	Labels	+/-	Modified files (first 100)	📝	💬	All users who commented or reviewed	Assignee(s)	Updated	Last status change	total time in review
14563	awueth author:awueth	feat: if-then-else of exclusive or statement	--- If `¬(P ∧ Q)` then `ite (P ∨ Q) a 1 = (ite P a 1) * (ite Q a 1)` [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-algebra new-contributor label:t-algebra$	5/0	Mathlib/Algebra/Group/Basic.lean	1	3	['eric-wieser', 'github-actions', 'kim-em']	nobody	566-41185 1 year ago	566-41185 1 year ago	0-0 0 seconds
12751	Command-Master author:Command-Master	feat: add lemmas for Nat/Bits, Nat/Bitwise and Nat/Size	Remove `@[simp]` from `Nat.bit_false` and `Nat.bit_true`, as `bit0` and `bit1` are deprecated, and add some lemmas to `Bits`, `Bitwise` and `Size`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor t-data	66/7	Mathlib/Data/Nat/Bits.lean,Mathlib/Data/Nat/Bitwise.lean,Mathlib/Data/Nat/Multiplicity.lean,Mathlib/Data/Nat/Size.lean	4	26	['Command-Master', 'Rida-Hamadani', 'Ruben-VandeVelde', 'YaelDillies', 'github-actions', 'jcommelin']	nobody	562-26094 1 year ago	567-42336 1 year ago	0-0 0 seconds
15121	Eloitor author:Eloitor	feat: iff theorems for IsSplitEpi and IsSplitMono in opposite category	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-category-theory new-contributor	40/0	Mathlib/CategoryTheory/EpiMono.lean	1	3	['github-actions', 'joelriou', 'mattrobball']	nobody	549-929 1 year ago	580-46588 1 year ago	0-0 0 seconds
14242	js2357 author:js2357	feat: Prove equivalence of `isDedekindDomain` and `isDedekindDomainDvr`	Prove that `isDedekindDomainDvr` is equivalent to both `isDedekindDomain` and `isDedekindDomainInv`. Specifically, prove `isDedekindDomainDvr A → isDedekindDomainInv A`, because `isDedekindDomain A → isDedekindDomainDvr A` and `IsDedekindDomain A ↔ IsDedekindDomainInv A` are already in Mathlib. - [x] depends on: #14099 - [x] depends on: #14216 - [ ] depends on: #14237 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-algebra new-contributor label:t-algebra$	269/1	Mathlib.lean,Mathlib/RingTheory/DedekindDomain/Dvr.lean,Mathlib/RingTheory/FractionalIdeal/LocalizedAtPrime.lean,Mathlib/RingTheory/Localization/Basic.lean	4	2	['github-actions', 'leanprover-community-mathlib4-bot']	nobody	526-11988 1 year ago	526-11988 1 year ago	0-0 0 seconds
16887	metinersin author:metinersin	feat(ModelTheory/Complexity): define conjunctive and disjunctive formulas	Defines `FirstOrder.Language.BoundedFormula.IsConjunctive` and `FirstOrder.Language.BoundedFormula.IsDisjunctive`. --- - [ ] depends on: #16885 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-logic new-contributor	300/7	Mathlib/ModelTheory/Complexity.lean,Mathlib/ModelTheory/Equivalence.lean,Mathlib/ModelTheory/Syntax.lean	3	2	['github-actions', 'mathlib4-dependent-issues-bot']	nobody	518-7966 1 year ago	518-7967 1 year ago	0-0 0 seconds
16888	metinersin author:metinersin	feat(ModelTheory/Complexity): Define conjunctive and disjunctive normal forms	Define `FirstOrder.Language.BoundedFormula.IsDNF` and `FirstOrder.Language.BoundedFormula.IsCNF`. --- - [ ] depends on: #16887 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-logic new-contributor	415/7	Mathlib/ModelTheory/Complexity.lean,Mathlib/ModelTheory/Equivalence.lean,Mathlib/ModelTheory/Syntax.lean	3	2	['github-actions', 'mathlib4-dependent-issues-bot']	nobody	518-7966 1 year ago	518-7966 1 year ago	0-0 0 seconds
16889	metinersin author:metinersin	feat(ModelTheory/Complexity): Normal forms	Defines `FirstOrder.Language.BoundedFormula.toDNF` and `FirstOrder.Language.BoundedFormula.toCNF` - given a quantifier-free formula, these construct a semantically equivalent formula in disjunctive normal form and conjunctive normal form, respectively. --- - [ ] depends on: #16888 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-logic new-contributor	525/7	Mathlib/ModelTheory/Complexity.lean,Mathlib/ModelTheory/Equivalence.lean,Mathlib/ModelTheory/Syntax.lean	3	2	['github-actions', 'mathlib4-dependent-issues-bot']	nobody	518-7965 1 year ago	518-7965 1 year ago	0-0 0 seconds
12750	Command-Master author:Command-Master	feat: define Gray code	--- Define binary reflected gray code, both as a permutation of `Nat` and as a permutation of `BitVec n`, and prove some theorems about them. Additionally, remove `@[simp]` from `Nat.bit_false` and `Nat.bit_true`, as `bit0` and `bit1` are deprecated, and add some lemmas to `Bits`, `Bitwise` and `Size`. - [ ] depends on: #12751 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR awaiting-author merge-conflict new-contributor t-data	226/0	Mathlib.lean,Mathlib/Data/Nat/Bits.lean,Mathlib/Data/Nat/Bitwise.lean,Mathlib/Data/Nat/GrayCode.lean,Mathlib/Data/Nat/Size.lean	5	5	['Rida-Hamadani', 'alreadydone', 'github-actions', 'grunweg', 'leanprover-community-mathlib4-bot']	nobody	500-30623 1 year ago	500-30623 1 year ago	0-0 0 seconds
14603	awueth author:awueth	feat: degree is invariant under graph isomorphism	--- Mathlib has the definition `SimpleGraph.Iso.mapNeighborSet` which is an equivalence between neighbor sets induced by an isomorphism. Would it be beneficial to add the same equivalence for `neighborFinset`? [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP t-combinatorics new-contributor	24/0	Mathlib/Combinatorics/SimpleGraph/Map/Finite.lean	1	11	['awueth', 'github-actions', 'jcommelin', 'kim-em', 'urkud']	nobody	498-19931 1 year ago	498-19931 1 year ago	0-0 0 seconds
9605	davikrehalt author:davikrehalt	feat(Data/Finset & List): Add Lemmas for Sorting and Filtering	This PR includes several useful lemmas to the Data/Finset and Data/List modules in Lean's mathlib: 1. `toFinset_filter` (List): Shows that filtering commutes with toFinset. 2. `toFinset_is_singleton_implies_replicate` (List): Shows a list with a singleton toFinset is a List.replicate. 3. `filter_sort_commute` (Finset): Sorting and filtering can be interchanged in Finsets. 4. `Sorted.filter` (List): A sorted list stays sorted after filtering. 5. `Sorted.append_largest` (List): Appending the largest element keeps a list sorted. 6. `sort_monotone_map` (Finset): Relates sorting of a Finset after mapping to sorting of a list. 7. `sort_insert_largest` (Finset): Sorting a Finset with an inserted largest element. 8. `sort_range` (Finset): Sorting a range in a Finset equals the corresponding range list. 9. ~~`filter_eval_true` (List): Filtering a list with a predicate always true keeps the list unchanged.~~ 10. ~~`filter_eval_false` (List): Filtering with an always-false predicate gives an empty list.~~ 11. ~~`pairwise_concat` (List): Iff condition for Pairwise relation in concatenated lists (similar to pairwise_join).~~ 12. `list_map_toFinset` (Finset): toFinset commutes with map under injection --- - [x] depends on: #15952 This is my first PR to mathlib, so I'm not too familiar with etiquette's and more specifically there are two proofs in the PR which uses aesop, and I am not sure if it's frowned upon. I kept the aesop in there for now as I couldn't construct very short proofs otherwise. The sort_range function proof was suggested in https://leanprover.zulipchat.com/#narrow/stream/113489-new-members/topic/Computing.20Finset.20sort.20of.20Finset.20range/near/410346731 by Ruben Van de Velde. Thanks for your time for improving this PR.	awaiting-author please-adopt merge-conflict new-contributor t-data	71/0	Mathlib/Data/Finset/Basic.lean,Mathlib/Data/Finset/Image.lean,Mathlib/Data/Finset/Sort.lean,Mathlib/Data/List/Sort.lean	4	30	['YaelDillies', 'davikrehalt', 'eric-wieser', 'github-actions', 'jcommelin', 'leanprover-community-mathlib4-bot', 'urkud', 'vihdzp']	YaelDillies assignee:YaelDillies	490-1933 1 year ago	516-57124 1 year ago	0-0 0 seconds
14598	Command-Master author:Command-Master	chore: add typeclasses to unify various `add_top`, `add_eq_top`, etc.	Add the four typeclasses `IsTopAbsorbing`, `IsBotAbsorbing`, `NoTopSum`, `NoBotSum`, as additive equivalents for `MulZeroClass` and `NoZeroDivisors`. Add instances of these for `ENNReal`, `WithTop α`, `WithBot α`, `PUnit`, `EReal`, `PartENat`, `Measure`, `Interval` and `Filter`. Also split `Algebra/Order/AddGroupWithTop` to `Algebra/Order/Group/WithTop` and `Algebra/Order/Monoid/WithTop` --- Previous usages of lemmas with quantified names like `WithTop.add_top` have to be changed to just `add_top`. `add_lt_top` is `@[simp]`, in accordance with `ENNReal.add_lt_top` being `@[simp]`. This affects `WithTop.add_lt_top` which previously hadn't been `@[simp]`. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra t-order new-contributor label:t-algebra$	264/195	Archive/Wiedijk100Theorems/BallotProblem.lean,Mathlib.lean,Mathlib/Algebra/Order/Group/WithTop.lean,Mathlib/Algebra/Order/GroupWithZero/Canonical.lean,Mathlib/Algebra/Order/Interval/Basic.lean,Mathlib/Algebra/Order/Monoid/Unbundled/Basic.lean,Mathlib/Algebra/Order/Monoid/Unbundled/Defs.lean,Mathlib/Algebra/Order/Monoid/Unbundled/WithTop.lean,Mathlib/Algebra/Order/Monoid/WithTop.lean,Mathlib/Algebra/PUnitInstances/Order.lean,Mathlib/Algebra/Polynomial/Degree/Definitions.lean,Mathlib/Algebra/Polynomial/Monic.lean,Mathlib/Algebra/Tropical/Basic.lean,Mathlib/Analysis/Analytic/Meromorphic.lean,Mathlib/Analysis/Normed/Lp/ProdLp.lean,Mathlib/Analysis/NormedSpace/ENorm.lean,Mathlib/Analysis/SpecialFunctions/JapaneseBracket.lean,Mathlib/Analysis/SpecialFunctions/Log/ENNRealLog.lean,Mathlib/Data/ENNReal/Operations.lean,Mathlib/Data/ENat/Basic.lean,Mathlib/Data/Nat/PartENat.lean,Mathlib/Data/Nat/WithBot.lean,Mathlib/Data/Real/EReal.lean,Mathlib/LinearAlgebra/Lagrange.lean,Mathlib/MeasureTheory/Covering/Differentiation.lean,Mathlib/MeasureTheory/Decomposition/Lebesgue.lean,Mathlib/MeasureTheory/Function/ConditionalExpectation/CondexpL1.lean,Mathlib/MeasureTheory/Function/Jacobian.lean,Mathlib/MeasureTheory/Function/L1Space.lean,Mathlib/MeasureTheory/Function/L2Space.lean,Mathlib/MeasureTheory/Function/LpSeminorm/Basic.lean,Mathlib/MeasureTheory/Function/LpSeminorm/TriangleInequality.lean,Mathlib/MeasureTheory/Function/LpSpace.lean,Mathlib/MeasureTheory/Function/StronglyMeasurable/Basic.lean,Mathlib/MeasureTheory/Function/UniformIntegrable.lean,Mathlib/MeasureTheory/Integral/Bochner.lean,Mathlib/MeasureTheory/Integral/MeanInequalities.lean,Mathlib/MeasureTheory/Integral/SetIntegral.lean,Mathlib/MeasureTheory/Integral/VitaliCaratheodory.lean,Mathlib/MeasureTheory/Measure/Hausdorff.lean,Mathlib/MeasureTheory/Measure/Lebesgue/Basic.lean,Mathlib/MeasureTheory/Measure/LevyProkhorovMetric.lean,Mathlib/MeasureTheory/Measure/MeasureSpace.lean,Mathlib/MeasureTheory/Measure/MeasureSpaceDef.lean,Mathlib/MeasureTheory/Measure/Regular.lean,Mathlib/MeasureTheory/Measure/Typeclasses.lean,Mathlib/NumberTheory/Padics/PadicNumbers.lean,Mathlib/Order/Filter/Pointwise.lean,Mathlib/Probability/Kernel/Defs.lean,Mathlib/Probability/Martingale/Convergence.lean,Mathlib/RingTheory/Multiplicity.lean,Mathlib/RingTheory/MvPowerSeries/NoZeroDivisors.lean,Mathlib/RingTheory/UniqueFactorizationDomain.lean,Mathlib/Topology/EMetricSpace/Defs.lean,Mathlib/Topology/MetricSpace/Bounded.lean,Mathlib/Topology/MetricSpace/HausdorffDistance.lean,Mathlib/Topology/MetricSpace/Lipschitz.lean	57	30	['Command-Master', 'YaelDillies', 'github-actions']	nobody	483-58899 1 year ago	483-58899 1 year ago	0-0 0 seconds
16885	metinersin author:metinersin	feat(ModelTheory/Complexity): define literals	Defines `FirstOrder.Language.BoundedFormula.IsLiteral` and `FirstOrder.Language.BoundedFormula.simpleNot` - an auxiliary operation that takes the negation of a formula and does some simplification. --- - [x] depends on: #16800 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-logic new-contributor	148/5	Mathlib/ModelTheory/Complexity.lean,Mathlib/ModelTheory/Equivalence.lean,Mathlib/ModelTheory/Semantics.lean,Mathlib/ModelTheory/Syntax.lean	4	20	['YaelDillies', 'awainverse', 'github-actions', 'mathlib4-dependent-issues-bot', 'metinersin']	nobody	481-15020 1 year ago	481-15020 1 year ago	0-0 0 seconds
13248	hcWang942 author:hcWang942	feat: basic concepts of auction theory	## Description Formalise some core concepts and results in auction theory: this includes definitions for first-price and second-price auctions, as well as several fundamental results and helping lemmas. This is the very first PR of the project formalizing core concepts and results in auction theory. Our group is working on more contributions on the formalization of game theory prefix. Co-authored-by: Ma Jiajun ## Reference Roughgarden, Tim. *Twenty Lectures on Algorithmic Game Theory*. Cambridge University Press, 2020. [Link](https://www.cambridge.org/core/books/twenty-lectures-on-algorithmic-game-theory/A9D9427C8F43E7DAEF8C702755B6D72B) --- - [x] Will depend on #14163 once that PR is merged. The Fintype lemmas introduced by this PR have been added in that PR and will be removed from here once that PR gets merged ## Current plan for formalization of Game Theory The current plan for the formalizing of Game Theory include: #### 1. Auction Theory. 🎉 _(200+ lines, this PR)_ - Essential definitions of Sealed-bid auction, First-price auction and Second-price auction. - First-price auction has no dominant strategy. - Second-price auction has dominant strategy. (Second-price auction is DSIC) #### 2. Mechanism design & Myerson's Lemma. 🎉 (400+ lines, pending for modification to Mathlib Standard) - Mechanism design An allocation rule is implementable if there exists - Dominant Strategy Incentive Compatible (DSIC) payment rule - An allocation rule is monotone if for every bidder’s gain is nondecreasing w.r.t. her/his bid - Myerson's Lemma Implementable ⇔ Monotone In the above case, the DSIC payment rule is unique. #### 3. von Neumann‘s Minimax Theorem. 🎉 (800+ lines, pending for modification to Mathlib Standard) - Equilibrium in zero sum game - Formalization strategy: via Loomis’s theorem. #### 4. Nash Equilibrium. 🎉 (pending for modification to Mathlib Standard) #### 5. Brouwer fixed-point theorem. (Work in Progress) #### 6. More Mechanism design. (Planning)	awaiting-author merge-conflict t-logic new-contributor	204/0	Mathlib.lean,Mathlib/GameTheory/Auction/Basic.lean,docs/references.bib	3	148	['Shreyas4991', 'YaelDillies', 'eric-wieser', 'faenuccio', 'github-actions', 'grunweg', 'hcWang942', 'tb65536', 'urkud', 'vihdzp']	hcWang942 assignee:hcWang942	476-53852 1 year ago	unknown	unknown
19125	yhtq author:yhtq	feat: add theorems to transfer `IsGalois` between pairs of fraction rings	feat: add theorems to transfer `IsGalois` between pairs of fraction rings. - [x] depends on: #18404 - [x] depends on: #19124 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra new-contributor label:t-algebra$	121/0	Mathlib.lean,Mathlib/FieldTheory/Galois/IsFractionRing.lean,Mathlib/RingTheory/Localization/FractionRing.lean	3	3	['github-actions', 'mathlib4-dependent-issues-bot', 'tb65536']	nobody	446-76269 1 year ago	453-25292 1 year ago	0-0 0 seconds
17739	Aaron1011 author:Aaron1011	feat(Topology/Order/DenselyOrdered): prove Not (IsOpen) for intervals	Prove that Iic/Ici/Ioc/Ico/Icc intervals are not open in densely ordered topologies with no min/max element --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-topology new-contributor	27/0	Mathlib/Topology/Order/DenselyOrdered.lean	1	8	['github-actions', 'vihdzp']	nobody	413-11881 1 year ago	413-11881 1 year ago	0-0 0 seconds
15711	znssong author:znssong	feat(Combinatorics/SimpleGraph): Some lemmas about walk, cycle and Hamiltonian cycle	--- These lemmas are separated from the `meow-sister/BondyChvatal` branch and will be needed for the proof of the Bondy-Chvátal theorem. - [x] depends on: #15536 - [x] depends on: #16294	awaiting-author merge-conflict t-combinatorics new-contributor	407/3	Mathlib/Combinatorics/SimpleGraph/Finite.lean,Mathlib/Combinatorics/SimpleGraph/Hamiltonian.lean,Mathlib/Combinatorics/SimpleGraph/Path.lean,Mathlib/Combinatorics/SimpleGraph/Walk.lean	4	22	['Rida-Hamadani', 'YaelDillies', 'github-actions', 'mathlib4-dependent-issues-bot', 'znssong']	nobody	412-30967 1 year ago	412-30967 1 year ago	0-0 0 seconds
15720	znssong author:znssong	feat(SimpleGraph): The Bondy-Chvátal theorem	The proof of the Bondy-Chvátal theorem, with Dirac's theorem and Ore's theorem as its corollary. - [x] depends on: #15536 - [ ] depends on: #15711 - [ ] depends on: #15578	blocked-by-other-PR merge-conflict t-combinatorics new-contributor	903/3	Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/BondyChvatal.lean,Mathlib/Combinatorics/SimpleGraph/Finite.lean,Mathlib/Combinatorics/SimpleGraph/Hamiltonian.lean,Mathlib/Combinatorics/SimpleGraph/Path.lean,Mathlib/Combinatorics/SimpleGraph/Walk.lean,Mathlib/Dynamics/FixedPoints/Basic.lean,Mathlib/Dynamics/FixedPoints/Increasing.lean	8	3	['github-actions', 'grunweg', 'leanprover-community-mathlib4-bot']	YaelDillies assignee:YaelDillies	412-30967 1 year ago	412-30967 1 year ago	0-0 0 seconds
18629	tomaz1502 author:tomaz1502	feat(Computability.Timed): Formalization of runtime complexity of List.merge	This PR adds the formalization of the runtime complexity of the merge function, defined in `Data/List/Sort`. Requires: https://github.com/leanprover-community/mathlib4/pull/15450 References: - Previous PR on mathlib3: https://github.com/leanprover-community/mathlib3/pull/14494/ - First discussion on Zulip: https://leanprover.zulipchat.com/#narrow/stream/113488-general/topic/BSc.20Final.20Project/near/220647062 - Second disussion on Zulip: https://leanprover.zulipchat.com/#narrow/stream/113488-general/topic/Formalization.20of.20Runtime.20Complexity.20of.20Sorting.20Algorithms/near/284184450 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict new-contributor t-computability	186/0	Mathlib.lean,Mathlib/Computability/Timed/InsertionSort.lean,Mathlib/Computability/Timed/Merge.lean	3	2	['github-actions', 'trivial1711']	nobody	411-83286 1 year ago	411-83286 1 year ago	0-0 0 seconds
18461	hannahfechtner author:hannahfechtner	feat: left and right common multiples mixins	add mixins for left and right common multiples. These carry the data of what factors are used to create the common multiples --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-algebra new-contributor label:t-algebra$	78/0	Mathlib/Algebra/Group/Defs.lean	1	13	['github-actions', 'hannahfechtner', 'jcommelin', 'kbuzzard', 'kim-em', 'trivial1711']	nobody	408-44466 1 year ago	408-44466 1 year ago	0-0 0 seconds
19291	PieterCuijpers author:PieterCuijpers	feat(Algebra/Order/Hom): add quantale homomorphism	Definition of quantale homomorphisms as functions that are both semigroup homomorphisms and complete lattice homomorphisms. --- - [x] depends on: #19810 - [x] depends on: #19811 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-algebra new-contributor label:t-algebra$	209/0	Mathlib.lean,Mathlib/Algebra/Order/Hom/Quantale.lean,scripts/noshake.json	3	29	['PieterCuijpers', 'YaelDillies', 'github-actions', 'kim-em', 'mathlib4-dependent-issues-bot']	nobody	407-18545 1 year ago	407-18546 1 year ago	0-0 0 seconds
20372	jvlmdr author:jvlmdr	feat(MeasureTheory/Function): Add ContinuousLinearMap.bilinearCompLp(L)	Introduce ContinuousLinearMap.bilinearCompLp and bilinearCompLpL. Generalize eLpNorm_le_eLpNorm_mul_eLpNorm theorems to include constant C in bound condition. --- Expect this may be useful for defining tempered distributions from functions in `L^p`. The definitions more or less follow `ContinuousLinearMap.compLp...`. Names are loosely analogous to `ContinuousLinearMap.bilinearComp` and `SchwartzMap.bilinLeftCLM`. Note: I preferred the spelling `hpqr : p⁻¹ + q⁻¹ = r⁻¹` with `f` in `L^p` and `g` in `L^q` to `hpqr : 1 / p = 1 / q + 1 / r`. It's easier to obtain from `ENNReal.IsConjExponent` too. A few questions: - [ ] I defined `bilinear{Left,Right}LpL` in addition to `bilinearCompLpL` because `LinearMap.mkContinuous₂` is marked as `noncomputable` and `LinearMap.mkContinuous` is not. Is this worth the extra definitions? (Note: This is not visible in the source due to `noncomputable section`.) - [ ] Should I use `C : ℝ` instead of `C : NNReal` for `eLpNorm_le_eLpNorm_mul_eLpNorm'_of_norm'`? - [ ] Is it going to be painful to have `[Fact (1 ≤ p)] [Fact (1 ≤ q)] [Fact (1 ≤ r)]`? I don't think there's a way to avoid it though. Maybe providing specialized versions for `p.IsConjExponent q` with `L^1`? Naming: - [ ] Is it satisfactory to add a `'` to the `eLpNorm_le_eLpNorm_mul_eLpNorm ` definitions in `CompareExp.lean` where `≤ ‖f x‖ * ‖g x‖` has been replaced with `≤ C * ‖f x‖ * ‖g x‖`? These could replace the existing theorems, although I don't want to break backwards compatibility. There are 5 instances: `eLpNorm_le_eLpNorm_top_mul_eLpNorm'`, `eLpNorm_le_eLpNorm_mul_eLpNorm_top'`, `eLpNorm'_le_eLpNorm'_mul_eLpNorm''`, `eLpNorm_le_eLpNorm_mul_eLpNorm_of_nnnorm'`, `eLpNorm_le_eLpNorm_mul_eLpNorm'_of_norm'` (I'm not sure why the existing theorem `eLpNorm_le_eLpNorm_mul_eLpNorm'_of_norm` has an internal `'`) - [ ] Is `bilinearLeftLpL` a suitable name? Other options: `bilinearCompLpLeftL`, `bilinearCompLeftLpL`, `bilinLeftLpL` (analogous to `SchwartzMap.bilinLeftCLM`) [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-measure-probability new-contributor	203/40	Mathlib/MeasureTheory/Function/LpSeminorm/CompareExp.lean,Mathlib/MeasureTheory/Function/LpSpace.lean	2	1	['github-actions']	nobody	400-35893 1 year ago	400-35893 1 year ago	0-0 0 seconds
20248	peabrainiac author:peabrainiac	feat(Topology/Compactness): first-countable locally path-connected spaces are delta-generated	Shows that all first-countable locally path-connected spaces are delta-generated (so in particular all normed spaces and convex subsets thereof are), and that delta-generated spaces are equivalently generated by the unit interval or standard simplices. --- - [ ] depends on: #21616 In principle, this should be close to all that's required to show that all simplicial complexes and CW-complexes are delta-generated; I just haven't done it yet because I'm not sure which file to best do it in. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR awaiting-author merge-conflict t-topology new-contributor large-import	1189/813	Mathlib.lean,Mathlib/Geometry/Manifold/ChartedSpace.lean,Mathlib/Topology/Algebra/Module/LocallyConvex.lean,Mathlib/Topology/Compactness/DeltaGeneratedSpace.lean,Mathlib/Topology/Connected/LocPathConnected.lean,Mathlib/Topology/Connected/PathConnected.lean,Mathlib/Topology/ContinuousOn.lean,Mathlib/Topology/Homotopy/HSpaces.lean,Mathlib/Topology/Path.lean	9	22	['YaelDillies', 'github-actions', 'kbuzzard', 'mathlib4-dependent-issues-bot', 'peabrainiac']	nobody	387-79603 1 year ago	387-79603 1 year ago	0-0 0 seconds
19943	AlexLoitzl author:AlexLoitzl	feat(Computability): Add Chomsky Normal Form Grammar and translation	- Define Chomsky normal form grammars - Add language-preserving translation between context-free grammars and Chomsky normal form grammars Co-authored-by: Martin Dvorak martin.dvorak@matfyz.cz --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict new-contributor t-computability	3151/0	Mathlib.lean,Mathlib/Computability/ChomskyNormalForm/Basic.lean,Mathlib/Computability/ChomskyNormalForm/EmptyElimination.lean,Mathlib/Computability/ChomskyNormalForm/LengthRestriction.lean,Mathlib/Computability/ChomskyNormalForm/TerminalRestriction.lean,Mathlib/Computability/ChomskyNormalForm/Translation.lean,Mathlib/Computability/ChomskyNormalForm/UnitElimination.lean,Mathlib/Computability/ContextFreeGrammar.lean	8	59	['AlexLoitzl', 'YaelDillies', 'github-actions', 'kim-em', 'madvorak']	nobody	383-27302 1 year ago	383-27302 1 year ago	0-0 0 seconds
21501	sksgurdldi author:sksgurdldi	feat(List): add sum_zipWith_eq_finset_sum	### Description: This PR adds the lemma `List.sum_zipWith_eq_finset_sum` to `Mathlib.Algebra.BigOperators.Group.Finset.Basic`. #### Statement: The sum of the `zipWith` operation on two lists equals the sum of applying the operation to corresponding elements of the two lists, indexed over the minimum of their lengths. #### Formal Statement: ```lean lemma sum_zipWith_eq_finset_sum [Inhabited α] [Inhabited β] [AddCommMonoid γ] {op : α → β → γ} (l : List α) (m : List β) : (List.zipWith op l m).sum = ∑ x ∈ (Finset.range (Nat.min l.length m.length)), op (l[x]!) (m[x]!) ``` #### Remarks: - This lemma provides a useful equivalence between `List.zipWith` and summation over a `Finset.range` indexed by `Nat.min l.length m.length`. - It can be helpful in algebraic manipulations involving list-based summations. #### Dependencies: No additional dependencies. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-algebra new-contributor label:t-algebra$	43/0	Mathlib/Algebra/BigOperators/Group/Finset/Basic.lean	1	1	['github-actions', 'j-loreaux']	nobody	377-82473 1 year ago	377-82473 1 year ago	0-0 0 seconds
14313	grhkm21 author:grhkm21	feat(RepresentationTheory/FdRep): FdRep is a full subcategory of Rep	``` /-- Equivalence between `FDRep` and the full subcategory of finite dimensional `Rep`. -/ def equivFiniteDimensional : FDRep k G ≌ FullSubcategory (fun V : Rep k G ↦ FiniteDimensional k V) ```	merge-conflict t-category-theory t-algebra new-contributor label:t-algebra$	47/8	Mathlib/RepresentationTheory/FDRep.lean	1	19	['github-actions', 'grhkm21', 'joelriou', 'kim-em', 'mathlib-bors']	nobody	369-35900 1 year ago	369-35900 1 year ago	0-0 0 seconds
14060	YnirPaz author:YnirPaz	feat(SetTheory/Ordinal/Clubs): define club sets and prove basic properties	Create a file where club sets are defined and their basic properties are proven. I also created a new recursion principle for ordinals, bounded recursion. --- - [ ] depends on: #19189 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-logic new-contributor	315/3	Mathlib.lean,Mathlib/Order/SuccPred/Limit.lean,Mathlib/SetTheory/Cardinal/Cofinality.lean,Mathlib/SetTheory/Ordinal/Arithmetic.lean,Mathlib/SetTheory/Ordinal/Club.lean,Mathlib/SetTheory/Ordinal/Topology.lean	6	93	['YaelDillies', 'YnirPaz', 'alreadydone', 'dupuisf', 'github-actions', 'mathlib4-dependent-issues-bot', 'vihdzp', 'zeramorphic']	nobody	365-64724 1 year ago	365-64724 1 year ago	0-0 0 seconds
21959	BGuillemet author:BGuillemet	feat(Topology/ContinuousMap): Stone-Weierstrass theorem for MvPolynomial	Add the subalgebra of multivariate polynomials and prove it separates points, on the same model as `ContinuousMap/Polynomial.lean`. Prove the Stone-Weierstrass theorem and some variations for multivariate polynomials. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology new-contributor	285/1	Mathlib.lean,Mathlib/Topology/ContinuousMap/MvPolynomial.lean,Mathlib/Topology/ContinuousMap/StoneWeierstrass.lean	3	1	['github-actions']	nobody	364-21914 11 months ago	364-21914 11 months ago	0-0 0 seconds
15578	znssong author:znssong	feat(Function): Fixed points of function `f` with `f(x) >= x`	We added some lemmas of fixed points of function `f` with `f(x) >= x`, where `f : α → α` is a function on a finite type `α`. This will be needed in proof of Bondy-Chvátal theorem. --- See also branch `meow-sister/BondyChvatal`. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-analysis new-contributor	82/0	Mathlib.lean,Mathlib/Dynamics/FixedPoints/Basic.lean,Mathlib/Dynamics/FixedPoints/Increasing.lean	3	32	['Ruben-VandeVelde', 'YaelDillies', 'github-actions', 'urkud', 'vihdzp', 'znssong']	nobody	356-17740 11 months ago	356-17740 11 months ago	0-0 0 seconds
21018	markimunro author:markimunro	feat(Data/Matrix): add file with key definitions and theorems about elementary row operations	Prove that each elementary row operation is equivalent to a multiplication by an elementary matrix, has another row operation which inverts it, and that each elementary matrix has a left inverse. This is a very large PR and I understand it will take time. This is my first one and will likely have issues but I will be ready to answer questions/fix them as soon as possible. Co-authored-by: Christopher Lynch --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	enhancement awaiting-author merge-conflict new-contributor t-data	1230/0	Mathlib.lean,Mathlib/Data/Matrix/ElementaryRowOperations.lean,Mathlib/Data/Matrix/GaussianElimination.lean,Mathlib/Data/Matrix/GaussianEliminationOld,Mathlib/Data/Matrix/oldnames,et --hard 18533caba32,lean-toolchain	7	n/a	['chrisflav', 'eric-wieser', 'github-actions', 'j-loreaux', 'markimunro']	nobody	337-53139 11 months ago	unknown	unknown
15212	victorliu5296 author:victorliu5296	feat: Add fundamental theorem of calculus-2 for Banach spaces	add the Mean Value Theorem for Banach spaces to the library and include reference for the theorem statement This theorem states that if `f : X → Y` is differentiable along the line segment from `a` to `b`, then the change in `f` equals the integral of its derivative along this path. This extends the mean value theorem to Banach spaces. This can be used for the eventual proof of the Newton-Kantorovich theorem with 1 constant contained inside the added reference. Here is the discussion on Zulipchat: https://leanprover.zulipchat.com/#narrow/stream/287929-mathlib4/topic/Contributing.20FTC-2.20for.20Banach.20spaces	awaiting-author merge-conflict t-analysis t-measure-probability new-contributor	60/1	Mathlib/MeasureTheory/Integral/FundThmCalculus.lean	1	3	['github-actions', 'hrmacbeth', 'victorliu5296']	nobody	332-48128 10 months ago	332-48128 10 months ago	0-0 0 seconds
21488	imbrem author:imbrem	feat(CategoryTheory/Monoidal): premonoidal categories	Add support for premonoidal categories --- Still want to add support for: - Premonoidal braided/symmetric categories - The monoidal coherence theorem, which I've already ported in my `discretion` library - The `coherence` tactic, which should work fine for premonoidal categories too but wanted to get this in front of reviewers ASAP to make sure my general approach was alright [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-category-theory new-contributor	900/361	Mathlib/Algebra/Category/ModuleCat/Presheaf/Monoidal.lean,Mathlib/CategoryTheory/Bicategory/End.lean,Mathlib/CategoryTheory/GradedObject/Monoidal.lean,Mathlib/CategoryTheory/Localization/Monoidal.lean,Mathlib/CategoryTheory/Monoidal/Braided/Basic.lean,Mathlib/CategoryTheory/Monoidal/Category.lean,Mathlib/CategoryTheory/Monoidal/Center.lean,Mathlib/CategoryTheory/Monoidal/CoherenceLemmas.lean,Mathlib/CategoryTheory/Monoidal/Discrete.lean,Mathlib/CategoryTheory/Monoidal/End.lean,Mathlib/CategoryTheory/Monoidal/Free/Basic.lean,Mathlib/CategoryTheory/Monoidal/Functor.lean,Mathlib/CategoryTheory/Monoidal/FunctorCategory.lean,Mathlib/CategoryTheory/Monoidal/Mon_.lean,Mathlib/CategoryTheory/Monoidal/Opposite.lean,Mathlib/CategoryTheory/Monoidal/Transport.lean,Mathlib/Tactic/CategoryTheory/Monoidal/Datatypes.lean,Mathlib/Tactic/CategoryTheory/Monoidal/Normalize.lean,Mathlib/Tactic/CategoryTheory/Monoidal/PureCoherence.lean,Mathlib/Tactic/CategoryTheory/MonoidalComp.lean,MathlibTest/StringDiagram.lean	21	9	['YaelDillies', 'github-actions', 'grunweg', 'imbrem', 'kim-em', 'leanprover-community-bot-assistant']	nobody	329-30316 10 months ago	329-30317 10 months ago	0-0 0 seconds
20873	vbeffara author:vbeffara	feat(Topology/Covering): path lifting and homotopy lifting	This proves the existence and uniqueness of path and homotopy lifts through covering maps. --- I tried to separate as much of the proof as possible into separate PRs (which are already in Mathlib now), but the proof here relies on a monolithic construction of an explicit lift along a well-chosen subdivision, in `partial_lift`, with associated definitions. Only one standalone lean file added. An older WIP PR #10084 by Junyan Xu @alreadydone proves similar results using a very similar construction for path lifting, with a different argument to obtain continuity for homotopy lifting. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-topology new-contributor	281/1	Mathlib.lean,Mathlib/Topology/Covering/Basic.lean,Mathlib/Topology/Covering/Lift.lean	3	9	['alreadydone', 'github-actions', 'grunweg', 'vbeffara']	nobody	328-33044 10 months ago	328-33044 10 months ago	0-0 0 seconds
20313	thefundamentaltheor3m author:thefundamentaltheor3m	feat(Data/Complex/Exponential): prove some useful results about the complex exponential.	This PR proves two basic results about the complex exponential: * `abs_exp_mul_I (x : ℂ) : abs (Complex.exp (I * x)) = Real.exp (-x.im)` * `one_sub_rexp_re_le_abs_one_sub_cexp (x : ℂ) : 1 - Real.exp x.re ≤ Complex.abs (1 - Complex.exp x)` Both results were proved as part of the sphere packing project. There's a chance they're too specific for mathlib, but I thought they were worth PRing anyway. Would it also be a good idea to tag `abs_exp_mul_I` with `simp`? Feedback/suggestions welcome. Note: `one_sub_rexp_re_le_abs_one_sub_cexp` was proved by Bhavik Mehta @b-mehta --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-analysis new-contributor	167/141	Mathlib.lean,Mathlib/Analysis/Complex/Basic.lean,Mathlib/Analysis/SpecialFunctions/Log/ERealExp.lean,Mathlib/Analysis/SpecialFunctions/Trigonometric/Chebyshev.lean,Mathlib/Data/Complex/Exponential/Defs.lean,Mathlib/Data/Complex/Exponential/Lemmas.lean,Mathlib/Data/Complex/ExponentialBounds.lean,Mathlib/Tactic/FunProp.lean,MathlibTest/Recall.lean,MathlibTest/positivity.lean	10	12	['b-mehta', 'github-actions', 'kim-em', 'thefundamentaltheor3m', 'trivial1711']	nobody	321-4242 10 months ago	321-4242 10 months ago	0-0 0 seconds
20730	kuotsanhsu author:kuotsanhsu	feat(LinearAlgebra/Matrix/SchurTriangulation): prove Schur decomposition/triangulation	`Matrix.schur_triangulation` shows that a matrix over an algebraically closed field is unitarily similar to an upper triangular matrix --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-algebra new-contributor label:t-algebra$	317/2	Mathlib.lean,Mathlib/LinearAlgebra/Matrix/Block.lean,Mathlib/LinearAlgebra/Matrix/SchurTriangulation.lean,Mathlib/Logic/Equiv/Basic.lean	4	14	['eric-wieser', 'github-actions', 'kim-em', 'kuotsanhsu']	nobody	321-374 10 months ago	321-374 10 months ago	0-0 0 seconds
22809	b-reinke author:b-reinke	feat: Category algebras and path algebras	This PR defines the category algebra of a linear category and path algebras of quivers. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP t-category-theory t-algebra new-contributor label:t-algebra$	218/0	Mathlib/Algebra/Ring/Assoc.lean,Mathlib/CategoryTheory/Linear/CategoryAlgebra.lean,Mathlib/Combinatorics/Quiver/PathAlgebra.lean,Mathlib/Data/DFinsupp/BigOperators.lean	4	2	['b-reinke', 'github-actions']	nobody	305-51213 10 months ago	305-51213 10 months ago	0-0 0 seconds
15654	TpmKranz author:TpmKranz	feat(Computability): language-preserving maps between NFA and RE	Map REs to NFAs via Thompson's construction and NFAs to REs using GNFAs Last chunk of #12648 --- - [ ] depends on: #15651 - [ ] depends on: #15649 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict new-contributor t-computability awaiting-zulip	985/2	Mathlib.lean,Mathlib/Computability/GNFA.lean,Mathlib/Computability/Language.lean,Mathlib/Computability/NFA.lean,Mathlib/Computability/RegularExpressions.lean,Mathlib/Data/FinEnum/Option.lean,docs/references.bib	7	3	['github-actions', 'leanprover-community-mathlib4-bot', 'meithecatte']	nobody	302-83892 9 months ago	302-83897 9 months ago	0-0 0 seconds
24008	meithecatte author:meithecatte	chore(EpsilonNFA): replace manual lemmas with @[simps]	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author new-contributor t-computability	2/24	Mathlib/Computability/EpsilonNFA.lean	1	2	['YaelDillies', 'github-actions', 'urkud']	nobody	297-43071 9 months ago	297-43071 9 months ago	0-0 0 seconds
23349	BGuillemet author:BGuillemet	feat: add LocallyLipschitzOn.lipschitzOnWith_of_isCompact and two small lemmas about Lipschitz functions	Main feat (in Mathlib/Topology/EMetricSpace/Basic.lean): if a function `f` from an extended pseudometric space to a pseudometric space is locally Lipschitz on a compact subset `s`, then `f` is Lipschitz on `s`. The theorem is true only when the codomain of `f` is a pseudometric space, so it needs imports from Mathlib/Topology/MetricSpace. Other small feat (in Mathlib/Analysis/Calculus/ContDiff/RCLike.lean): a function that is continuously differentiable on an open subset is locally Lipschitz on this subset. --- - [ ] depends on: #22890 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology new-contributor large-import	59/4	Mathlib/Analysis/Calculus/ContDiff/RCLike.lean,Mathlib/Topology/EMetricSpace/Lipschitz.lean	2	4	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot']	PatrickMassot assignee:PatrickMassot	281-15412 9 months ago	281-15414 9 months ago	0-0 0 seconds
12799	jstoobysmith author:jstoobysmith	feat(LinearAlgebra/UnitaryGroup): Add properties of Special Unitary Group	Add properties of the special unitary group, mirroring the properties of found in Algebra/Star/Unitary.lean. In particular, I add an instance of `specialUnitaryGroup` as a `Group`, `Star`, `InvolutiveStar`, and `StarMul`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author please-adopt merge-conflict t-algebra new-contributor label:t-algebra$	78/0	Mathlib/LinearAlgebra/UnitaryGroup.lean	1	8	['chrisflav', 'jcommelin', 'leanprover-community-bot-assistant']	nobody	270-73765 8 months ago	270-73767 8 months ago	0-0 0 seconds
20334	miguelmarco author:miguelmarco	feat: allow polyrith to use a local Singular/Sage install	Try to call a local install of Singular (either standalone or inside Sage) to find the witness for polyrith before trying to call the online sage cell server. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-meta new-contributor	171/48	Mathlib/Tactic/Polyrith.lean,scripts/polyrith_sage.py	2	16	['eric-wieser', 'github-actions', 'hanwenzhu', 'kim-em', 'miguelmarco', 'mkoeppe']	nobody	263-66318 8 months ago	383-44280 1 year ago	0-0 0 seconds
25218	kckennylau author:kckennylau	feat(AlgebraicGeometry): Tate normal form of elliptic curves	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebraic-geometry new-contributor awaiting-zulip	291/26	Mathlib.lean,Mathlib/AlgebraicGeometry/EllipticCurve/IsomOfJ.lean,Mathlib/AlgebraicGeometry/EllipticCurve/Modular/TateNormalForm.lean,Mathlib/AlgebraicGeometry/EllipticCurve/NormalForms.lean,Mathlib/AlgebraicGeometry/EllipticCurve/VariableChange.lean	5	31	['MichaelStollBayreuth', 'Multramate', 'acmepjz', 'github-actions', 'grunweg', 'kckennylau', 'leanprover-community-bot-assistant']	nobody	242-63079 7 months ago	242-63080 7 months ago	0-0 0 seconds
10541	Louddy author:Louddy	feat(Algebra/SkewMonoidAlgebra/Basic): add SkewMonoidAlgebra	# Skew Monoid algebras This file presents a skewed version of `Mathlib.Algebra.MonoidAlgebra.Basic`. ## Definition We define `SkewMonoidAlgebra k G := G →₀ k` attached with a skewed convolution product. Here, the product of two elements `f g : SkewMonoidAlgebra k G` is the finitely supported function whose value at `a` is the sum of `f x * (x • g y)` over all pairs `x, y` such that `x * y = a`. This will be used in a later PR to define skew polynomial rings. Co-authored-by: María Inés de Frutos Fernández <[mariaines.dff@gmail.com](mailto:mariaines.dff@gmail.com)> --- - [x] depends on: #15878 - [x] depends on: #19084 - [x] depends on: #22078 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP merge-conflict t-algebra new-contributor label:t-algebra$	1624/0	Mathlib.lean,Mathlib/Algebra/Group/InjSurj.lean,Mathlib/Algebra/SkewMonoidAlgebra/Basic.lean,Mathlib/Algebra/SkewMonoidAlgebra/Lift.lean	4	105	['AntoineChambert-Loir', 'Louddy', 'YaelDillies', 'eric-wieser', 'fpvandoorn', 'github-actions', 'mariainesdff', 'mathlib4-dependent-issues-bot', 'mattrobball']	AntoineChambert-Loir assignee:AntoineChambert-Loir	238-32157 7 months ago	238-32159 7 months ago	0-0 0 seconds
10190	jstoobysmith author:jstoobysmith	feat(AlgebraicTopology): add Augmented Simplex Category	- Added the definition of the category FinLinOrd of finite linear ordered sets. - Added the definition of the augmented simplex category `AugmentedSimplexCategory`, and showed it is the Skeleton of FinLinOrd. - Showed that the category of augmented simplicial objects defined as a comma category is equivalent to the category of functors from `AugmentedSimplexCategory^\op` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP merge-conflict t-category-theory new-contributor t-algebraic-topology	720/0	Mathlib.lean,Mathlib/AlgebraicTopology/AugmentedSimplexCategory.lean,Mathlib/AlgebraicTopology/SimplicialObject.lean,Mathlib/Order/Category/FinLinOrd.lean	4	5	['TwoFX', 'YaelDillies', 'joelriou', 'jstoobysmith']	nobody	216-35219 7 months ago	216-35219 7 months ago	0-0 0 seconds
25486	VTrelat author:VTrelat	feat(SetTheory/ZFC/Integers): define integers in ZFC	Extend the model of ZFC with integers following the converse direction as for naturals. We first define a type and then build a set. We finally show that both representations have coercions in both direction: - define a proper type `ZFInt` representing integers based on `ZFNat × ZFNat` and following the usual construction of integers - add theorems on usual algebraic properties of integers - define a set `Int` and show that it matches-i.e. that it is isomorphic to-the type `ZFInt` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) - [ ] depends on: #25483 - [ ] depends on: #25485	blocked-by-other-PR merge-conflict new-contributor t-set-theory	2003/0	Mathlib/Data/Set/Prod.lean,Mathlib/SetTheory/ZFC/Basic.lean,Mathlib/SetTheory/ZFC/Booleans.lean,Mathlib/SetTheory/ZFC/Integers.lean	4	3	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot']	nobody	212-41444 7 months ago	212-41444 7 months ago	0-0 0 seconds
25485	VTrelat author:VTrelat	feat(SetTheory/ZFC/Naturals): define natural numbers in ZFC	Extend the model of ZFC with naturals: - define a set `Nat` of naturals following the usual construction (∅, {∅}, {∅, {∅}}, ...) - define a proper type `ZFNat` representing naturals - add theorems on usual algebraic properties of naturals - provide a recursor and induction schemes to define/prove by induction --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) - [ ] depend on: #25483	merge-conflict new-contributor t-set-theory	2095/0	Mathlib/Data/Set/Prod.lean,Mathlib/SetTheory/ZFC/Basic.lean,Mathlib/SetTheory/ZFC/Booleans.lean,Mathlib/SetTheory/ZFC/Naturals.lean	4	2	['github-actions', 'leanprover-community-bot-assistant']	nobody	212-41440 7 months ago	212-41440 7 months ago	0-0 0 seconds
25484	VTrelat author:VTrelat	feat(SetTheory/ZFC/Booleans): define Boolean algebra in ZFC	Extend the model of ZFC with Boolean algebra: - define a set 𝔹 of booleans - define a proper type `ZFBool` representing booleans - add theorems on usual algebraic properties of booleans - provide usual boolean notations like `⊤`, `⊥`, `∧`, `∨`, etc. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) - [ ] depends on: #25483	blocked-by-other-PR merge-conflict new-contributor t-set-theory	619/0	Mathlib/Data/Set/Prod.lean,Mathlib/SetTheory/ZFC/Basic.lean,Mathlib/SetTheory/ZFC/Booleans.lean	3	3	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot']	nobody	212-41435 7 months ago	212-41435 7 months ago	0-0 0 seconds
25238	Hagb author:Hagb	feat(Tactic/ComputeDegree): add support for scalar multiplication with different types	It would be able to deal with `a • (X : R[X])` where `a : S` is in a different type `S` with `[SMulZeroClass S R]`. --- - [x] depends on: #25237 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-meta new-contributor	17/5	Mathlib/Tactic/ComputeDegree.lean,MathlibTest/ComputeDegree.lean	2	3	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot']	nobody	212-41410 7 months ago	212-41410 7 months ago	0-0 0 seconds
18646	jxjwan author:jxjwan	feat(RingTheory): isotypic components	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor t-ring-theory	308/0	Mathlib/Order/CompactlyGenerated/Basic.lean,Mathlib/RingTheory/Isotypic.lean,Mathlib/RingTheory/SimpleModule.lean	3	1	['github-actions']	nobody	211-43431 6 months ago	211-43431 6 months ago	0-0 0 seconds
20671	thefundamentaltheor3m author:thefundamentaltheor3m	feat(Analysis/Asymptotics/SpecificAsymptotics): Proving that 𝛔ₖ(n) = O(nᵏ⁺¹)	This PR proves a result about the $\sigma_k(n)$ arithmetic function, namely, that it is $O\left(n^{k+1}\right)$. Main theorem: `theorem sigma_asymptotic (k : ℕ) : (fun n ↦ (σ k n : ℝ)) =O[atTop] (fun n ↦ (n ^ (k + 1) : ℝ))` This result was proved as part of the sphere packing project. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-number-theory new-contributor large-import	29/0	Mathlib/Analysis/Asymptotics/SpecificAsymptotics.lean	1	3	['b-mehta', 'github-actions', 'mathlib4-merge-conflict-bot']	b-mehta assignee:b-mehta	206-46972 6 months ago	206-46972 6 months ago	0-0 0 seconds
27226	xcloudyunx author:xcloudyunx	feat(Combinatorics/SimpleGraph): Add Subgraph.inclusion_edge_apply_coe and inclusion_edgeSet_apply_coe	This PR continues the work from #25248. Original PR: https://github.com/leanprover-community/mathlib4/pull/25248	awaiting-author t-combinatorics new-contributor	14/0	Mathlib/Combinatorics/SimpleGraph/Subgraph.lean	1	3	['b-mehta', 'github-actions', 'xcloudyunx']	b-mehta assignee:b-mehta	204-62718 6 months ago	204-76798 6 months ago	25-83942 25 days
22925	ggranberry author:ggranberry	feat(Mathlib/PlaceHolder/ToeplitzHausdorff): Toeplitz-Hausdorff	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted WIP awaiting-author t-analysis new-contributor will-close-soon	411/0	Mathlib/PlaceHolder/ToeplitzHausdorff.lean,Mathlib/PlaceHolder/ToeplitzHausdorff_v2.lean	2	11	['faenuccio', 'ggranberry', 'github-actions']	faenuccio assignee:faenuccio	203-38842 6 months ago	203-39045 6 months ago	0-0 0 seconds
25483	VTrelat author:VTrelat	chore(Data/Set/Prod, SetTheory/ZFC/Basic): add theorem prod_subset_of_prod and extend ZFC model	Required by @eric-wieser in #24281 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor t-data	103/0	Mathlib/Data/Set/Prod.lean,Mathlib/SetTheory/ZFC/Basic.lean	2	10	['Ruben-VandeVelde', 'VTrelat', 'github-actions', 'leanprover-community-bot-assistant']	nobody	203-28762 6 months ago	242-63069 7 months ago	0-0 0 seconds
28502	gilesgshaw author:gilesgshaw	feat(Logic/Basic): avoid unnecessary uses of choice	Certain proofs are modified to remove a dependence on the axoim of choice --- - [ ] depends on: #28623	blocked-by-other-PR awaiting-author merge-conflict t-logic new-contributor	83/74	Mathlib/Logic/Basic.lean	1	7	['Ruben-VandeVelde', 'eric-wieser', 'gilesgshaw', 'github-actions', 'kim-em', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	197-58468 6 months ago	197-58469 6 months ago	0-35689 9 hours
19582	yu-yama author:yu-yama	feat(GroupExtension/Abelian): define `OfMulDistribMulAction.equivH2`	Mainly defines: - `structure GroupExtension.OfMulDistribMulAction N G [MulDistribMulAction G N]`: group extensions of `G` by `N` where the multiplicative action of `G` on `N` is the conjugation - `structure GroupExtension.OfMulDistribMulActionWithSection N G [MulDistribMulAction G N]`: group extensions with specific choices of sections - `def GroupExtension.OfMulDistribMulAction.equivH2`: a bijection between the equivalence classes of group extensions and $H^2 (G, N)$ --- - [x] depends on: #20802 (split PR: contains changes to the `Defs` file) - [x] depends on: #20998 (split PR: mainly adds the `Basic` file) - [ ] depends on: #26670 (split PR: adds the first part of the `Abelian` file) Here is a relevant TODO in Mathlib: https://github.com/leanprover-community/mathlib4/blob/4e9fa40d7c480937e09cd6e47a591bd6f3b8be42/Mathlib/RepresentationTheory/GroupCohomology/LowDegree.lean#L46-L48 I would appreciate your comments. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-algebra new-contributor label:t-algebra$	750/14	Mathlib.lean,Mathlib/GroupTheory/GroupExtension/Abelian.lean,Mathlib/GroupTheory/GroupExtension/Defs.lean,docs/references.bib	4	5	['YaelDillies', 'erdOne', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	195-8576 6 months ago	195-8577 6 months ago	0-0 0 seconds
28150	Equilibris author:Equilibris	chore: clean up proofs typevec proofs	While adding variable universe corecs I found a lot of theorems in typevec that could do with a bit of a clean-up --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor t-data	24/26	Mathlib/Data/TypeVec.lean	1	7	['Equilibris', 'alexkeizer', 'github-actions', 'mathlib4-merge-conflict-bot']	nobody	193-80237 6 months ago	193-80238 6 months ago	13-49738 13 days
25488	VTrelat author:VTrelat	feat(SetTheory/ZFC/Rationals): define rationals in ZFC	Extend the model of ZFC with rationals: we define a proper type `ZFRat` representing integers based on pairs of `ZFInt` (enforcing the res to be nonzero) and following the usual construction of rationals. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) - [ ] depends on: #25483 - [ ] depends on: #25485 - [ ] depends on: #25486	blocked-by-other-PR merge-conflict new-contributor t-set-theory	2070/0	Mathlib/Data/Set/Prod.lean,Mathlib/SetTheory/ZFC/Basic.lean,Mathlib/SetTheory/ZFC/Booleans.lean,Mathlib/SetTheory/ZFC/Integers.lean,Mathlib/SetTheory/ZFC/Rationals.lean	5	3	['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot']	nobody	193-59594 6 months ago	193-59594 6 months ago	0-0 0 seconds
27403	MoritzBeroRoos author:MoritzBeroRoos	fix: replace probably erroneous usage of ⬝ (with old \cdot) by · (with \centerdot)	Discussion at [zulip](https://leanprover.zulipchat.com/#narrow/channel/270676-lean4/topic/.5Ccdot.20!.3D.20.5Ccenterdot). Currently the abbreviations \cdot and \centerdot resolve to different, with the naked eye nearly undistinguishable symbols (despite the c in cdot surely standing for center..). This pr replaces instances of ⬝ where · was probably meant. All of the replacement is in comments, except for the file bench_summary.lean which is used for priting the github benchmark results. Since this file is about scientific notation of numbers, sure · was meant to be used, not a rectangle. [Related](https://github.com/leanprover-community/mathlib4/pull/27399) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor	195/195	Mathlib/Algebra/ContinuedFractions/Computation/Approximations.lean,Mathlib/Algebra/DirectSum/Idempotents.lean,Mathlib/Algebra/Lie/Derivation/Basic.lean,Mathlib/Algebra/Module/Equiv/Basic.lean,Mathlib/AlgebraicGeometry/EllipticCurve/DivisionPolynomial/Basic.lean,Mathlib/Analysis/Analytic/Constructions.lean,Mathlib/Analysis/CStarAlgebra/CStarMatrix.lean,Mathlib/Analysis/Calculus/ContDiff/Basic.lean,Mathlib/Analysis/Calculus/ContDiff/Bounds.lean,Mathlib/Analysis/Calculus/FDeriv/Symmetric.lean,Mathlib/Analysis/Fourier/FourierTransformDeriv.lean,Mathlib/Analysis/InnerProductSpace/Dual.lean,Mathlib/Analysis/InnerProductSpace/PiL2.lean,Mathlib/Analysis/Normed/Unbundled/InvariantExtension.lean,Mathlib/Analysis/SpecialFunctions/Complex/CircleAddChar.lean,Mathlib/Combinatorics/Configuration.lean,Mathlib/Combinatorics/SimpleGraph/AdjMatrix.lean,Mathlib/Combinatorics/SimpleGraph/LapMatrix.lean,Mathlib/Data/Matrix/Block.lean,Mathlib/Data/Matrix/ConjTranspose.lean,Mathlib/Data/Matrix/Hadamard.lean,Mathlib/Data/Matrix/Mul.lean,Mathlib/Data/Matrix/Notation.lean,Mathlib/Data/Matrix/Reflection.lean,Mathlib/Data/Matrix/RowCol.lean,Mathlib/Data/Matrix/Vec.lean,Mathlib/FieldTheory/PurelyInseparable/PerfectClosure.lean,Mathlib/Geometry/Manifold/GroupLieAlgebra.lean,Mathlib/GroupTheory/Coxeter/Matrix.lean,Mathlib/LinearAlgebra/CrossProduct.lean,Mathlib/LinearAlgebra/Matrix/BilinearForm.lean,Mathlib/LinearAlgebra/Matrix/DotProduct.lean,Mathlib/LinearAlgebra/Matrix/Nondegenerate.lean,Mathlib/LinearAlgebra/Matrix/Orthogonal.lean,Mathlib/LinearAlgebra/Matrix/PosDef.lean,Mathlib/LinearAlgebra/Matrix/SchurComplement.lean,Mathlib/LinearAlgebra/Matrix/SesquilinearForm.lean,Mathlib/LinearAlgebra/Matrix/Trace.lean,Mathlib/LinearAlgebra/Multilinear/Basic.lean,Mathlib/LinearAlgebra/PerfectPairing/Matrix.lean,Mathlib/LinearAlgebra/Projectivization/Constructions.lean,Mathlib/NumberTheory/NumberField/ProductFormula.lean,Mathlib/NumberTheory/SiegelsLemma.lean,Mathlib/RingTheory/DividedPowers/SubDPIdeal.lean,Mathlib/SetTheory/Ordinal/Veblen.lean,Mathlib/Topology/Algebra/Module/Equiv.lean,Mathlib/Topology/Homeomorph/Lemmas.lean,Mathlib/Topology/Instances/Matrix.lean,scripts/bench_summary.lean	49	5	['eric-wieser', 'github-actions', 'grunweg', 'leanprover-community-bot-assistant']	nobody	193-59557 6 months ago	216-35479 7 months ago	7-54661 7 days
27399	MoritzBeroRoos author:MoritzBeroRoos	chore: replace every usage of ⬝ᵥ (with old \cdot) by ·ᵥ (with \centerdot)	Discussion at [zulip](https://leanprover.zulipchat.com/#narrow/channel/270676-lean4/topic/.5Ccdot.20!.3D.20.5Ccenterdot). Currently the abbreviations `\cdot` and `\centerdot` resolve to different, with the naked eye nearly undistinguishable symbols (despite the c in cdot surely standing for `center`..): - `\cdot` gives ⬝ [U+2B1D](https://www.compart.com/en/unicode/U+2B1D) "Black Very Small Square" - `\centerdot` gives · [U+00B7](https://www.compart.com/en/unicode/U+00B7) "Middle Dot" Mathlib mostly uses the `\centerdot` variant, except for the dotProduct notation and some probably unsuspecting people wanting \centerdot but getting \cdot in their comments and 6 uses of a notation using the raw `\cdot` without any subscript at `Mathlib\Topology\Homotopy\Product.lean`. This PR replaces the dot product `⬝ᵥ` with its `\centerdot` counterpart `·ᵥ`. The related PR [here](https://github.com/leanprover/vscode-lean4/pull/639) can then overwrite the `\cdot` abbreviation, to produce the same symbol as the `centerdot` abbreviation does. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor	133/133	Mathlib/Analysis/CStarAlgebra/CStarMatrix.lean,Mathlib/Analysis/InnerProductSpace/PiL2.lean,Mathlib/Combinatorics/Configuration.lean,Mathlib/Combinatorics/SimpleGraph/AdjMatrix.lean,Mathlib/Combinatorics/SimpleGraph/LapMatrix.lean,Mathlib/Data/Matrix/Block.lean,Mathlib/Data/Matrix/ConjTranspose.lean,Mathlib/Data/Matrix/Hadamard.lean,Mathlib/Data/Matrix/Mul.lean,Mathlib/Data/Matrix/Notation.lean,Mathlib/Data/Matrix/Reflection.lean,Mathlib/Data/Matrix/RowCol.lean,Mathlib/Data/Matrix/Vec.lean,Mathlib/LinearAlgebra/CrossProduct.lean,Mathlib/LinearAlgebra/Matrix/BilinearForm.lean,Mathlib/LinearAlgebra/Matrix/DotProduct.lean,Mathlib/LinearAlgebra/Matrix/Nondegenerate.lean,Mathlib/LinearAlgebra/Matrix/Orthogonal.lean,Mathlib/LinearAlgebra/Matrix/PosDef.lean,Mathlib/LinearAlgebra/Matrix/SchurComplement.lean,Mathlib/LinearAlgebra/Matrix/SesquilinearForm.lean,Mathlib/LinearAlgebra/Matrix/Trace.lean,Mathlib/LinearAlgebra/PerfectPairing/Matrix.lean,Mathlib/LinearAlgebra/Projectivization/Constructions.lean,Mathlib/Topology/Instances/Matrix.lean	25	6	['MoritzBeroRoos', 'eric-wieser', 'github-actions', 'leanprover-community-bot-assistant']	nobody	193-21389 6 months ago	216-35480 7 months ago	7-62439 7 days
27479	iu-isgood author:iu-isgood	feat: Abel's Binomial Theorem	We have formalized Abel's Binomial Theorem as part of an REU project. There are a few remaining sorrys, but we will finish them soon. I will edit this PR message later according to community rules. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author new-contributor t-data	326/0	Mathlib/Data/Nat/Choose/AbelBinomial.lean	1	28	['ElifUskuplu', 'FrankieNC', 'github-actions', 'iu-isgood']	nobody	193-21150 6 months ago	216-85447 7 months ago	0-533 8 minutes
26462	PSchwahn author:PSchwahn	feat(LinearAlgebra/Projection): add results about inverse of `Submodule.prodEquivOfIsCompl`	Add two theorems `Submodule.prodEquivOfIsCompl_symm_apply` and `Submodule.prodEquivOfIsCompl_symm_add`, which are API for `Submodule.prodEquivOfIsCompl`. We believe these theorems are useful; for example, we have used their statements in a [classification formalization project](https://github.com/LieLean/LowDimSolvClassification). Co-authored by: - [Viviana del Barco](https://github.com/vdelbarc) - [Gustavo Infanti](https://github.com/GuQOliveira) - [Exequiel Rivas](https://github.com/erivas) --- I am not sure whether the `prodEquivOfIsCompl_symm_apply` theorem should be tagged with `@[simp]`; this might lead to confluence issues. Opinions are welcome! [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-algebra new-contributor label:t-algebra$	10/0	Mathlib/LinearAlgebra/Projection.lean	1	7	['PSchwahn', 'github-actions', 'joelriou', 'kckennylau']	joelriou assignee:joelriou	176-78918 5 months ago	177-23621 5 months ago	73-43082 73 days
28623	gilesgshaw author:gilesgshaw	feat(Logic/Basic): minor additions and simplification of proofs	Add new theorems and simplify proofs. Specifically, we add the family of related theorems `apply_dite_iff_exists`, `apply_dite_iff_forall`, `apply_ite_iff_and` and `apply_ite_iff_or`. For each other 'family' of theorems in the file that is analogous to the above, we do the following - Simplify proofs where possible, e.g. by appealing to the new theorems - Complete the family, if any of the corresponding four are missing - Rename to ensure consistency with the above pattern ---	merge-conflict t-logic new-contributor	83/55	Archive/Examples/IfNormalization/Result.lean,Archive/Examples/IfNormalization/WithoutAesop.lean,Mathlib/Algebra/ContinuedFractions/Computation/Translations.lean,Mathlib/Algebra/MvPolynomial/Variables.lean,Mathlib/Algebra/Notation/Indicator.lean,Mathlib/LinearAlgebra/Matrix/Rank.lean,Mathlib/Logic/Basic.lean,Mathlib/MeasureTheory/Measure/WithDensity.lean,Mathlib/SetTheory/Ordinal/Notation.lean	9	12	['eric-wieser', 'gilesgshaw', 'github-actions', 'mathlib4-merge-conflict-bot', 'plp127']	awainverse assignee:awainverse	176-27420 5 months ago	176-27421 5 months ago	21-3001 21 days
25778	thefundamentaltheor3m author:thefundamentaltheor3m	feat: Monotonicity of `setIntegral` for nonnegative functions	This PR makes it easier to prove monotonicity of the Bochner integral on sets for nonnegative functions by removing the stronger assumption required by the general monotonicity lemma that both of the functions being compared must be integrable. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-measure-probability new-contributor	8/0	Mathlib/MeasureTheory/Integral/Bochner/Set.lean	1	6	['RemyDegenne', 'github-actions', 'sgouezel', 'thefundamentaltheor3m']	nobody	174-23142 5 months ago	265-30975 8 months ago	0-11893 3 hours
29588	Periecle author:Periecle	feat(Analysis/Complex/Residue): Implement residue theory for complex functions at isolated singularities	# Add basic residue theory for complex functions This PR introduces the residue theory implementation in mathlib. ## Main additions - `HasIsolatedSingularityAt f c`: Predicate for functions with isolated singularities at point `c` - `residue f c hf`: The residue of `f` at isolated singularity `c`, defined via circle integrals - Radius independence: `residue_eq_two_pi_I_inv_smul_circleIntegral` - residue equals normalized circle integral for any valid radius - Holomorphic residues: `residue_of_holomorphic` - functions holomorphic in a neighborhood have zero residue - Simple pole formula: `residue_simple_pole` - for `f(z) = (z-c)⁻¹ * g(z)`, residue equals `g(c)` ## Implementation notes - Builds on existing circle integral infrastructure in `CauchyIntegral.lean` - Uses `Classical.choose` to extract witness radius from isolated singularity condition - Comprehensive documentation with mathematical context and examples - Establishes foundation for residue theorem, argument principle, and other applications ## Examples included - `residue(1/z, 0) = 1` (canonical simple pole) - Radius independence demonstration - Zero residues for holomorphic functions This provides the essential building blocks for complex analysis and first step to formalize residue theory.	awaiting-author t-analysis new-contributor	383/0	Mathlib/Analysis/Complex/Residue/Basic.lean	1	17	['Periecle', 'github-actions', 'hrmacbeth', 'llllvvuu', 'loefflerd']	nobody	161-26620 5 months ago	172-28723 5 months ago	1-5255 1 day
26178	ppls-nd-prs author:ppls-nd-prs	feat(CategoryTheory/Limits): Fubini for products	We show that the product of products is a product indexed by the sigma type. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-category-theory new-contributor	17/0	Mathlib/CategoryTheory/Limits/Shapes/Products.lean	1	6	['chrisflav', 'github-actions', 'leanprover-community-bot-assistant', 'ppls-nd-prs', 'robin-carlier']	nobody	156-41664 5 months ago	242-60770 7 months ago	0-47665 13 hours
28630	Antidite author:Antidite	feat(Archive/Imo): right isosceles configuration in the complex plane	feat(Archive/Imo): right isosceles configuration in the complex plane This adds `Archive/Imo/Imo1975Q3.lean`, formalizing a triangle configuration with points A=0, B=1, C=z and auxiliary points R, P, Q built via complex rotations and sine-based scale factors. Main results: * `angle_and_distance`: ∠QRP = π/2 and dist Q R = dist R P. * Key identity `QRP_rot90`: (Q z).z − R.z = e^{iπ/2} · ((P z).z − R.z). Design/Style: * Minimal imports; module docstring; semantic lemma names; all definitions and theorems live under the namespace `IMO.TriangleConfig`. Moves: - (none) Deletions: - (none) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author new-contributor IMO	196/0	Archive.lean,Archive/Imo/Imo1975Q3.lean	2	36	['Antidite', 'LLaurance', 'github-actions', 'jsm28']	jsm28 assignee:jsm28	151-7410 5 months ago	151-7410 5 months ago	46-38383 46 days
16773	arulandu author:arulandu	feat(Probability/Distributions): formalize Beta distribution	Formalize Beta distribution, using Gamma distribution as a reference. Added real-valued beta wrapper, in the manner of gamma. Thanks to @EtienneC30 for help with casting real <-> complex. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-measure-probability new-contributor	286/1	Mathlib.lean,Mathlib/Analysis/SpecialFunctions/Gamma/Beta.lean,Mathlib/Probability/Distributions/Beta.lean	3	50	['EtienneC30', 'arulandu', 'github-actions', 'mathlib4-merge-conflict-bot', 'vihdzp']	arulandu assignee:arulandu	145-16715 4 months ago	147-29185 4 months ago	0-0 0 seconds
30460	janithamalith author:janithamalith	feat(Nat): add lemma nat_card_orbit_mul_card_stabilizer_eq_card_group	Added a lemma `nat_card_orbit_mul_card_stabilizer_eq_card_group` which is the Nat.card version of MulAction.card_orbit_mul_card_stabilizer_eq_card_group --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author new-contributor t-group-theory	6/0	Mathlib/GroupTheory/GroupAction/CardCommute.lean	1	17	['github-actions', 'kckennylau', 'plp127', 'tb65536']	tb65536 assignee:tb65536	135-26965 4 months ago	135-26965 4 months ago	8-8414 8 days
25225	xcloudyunx author:xcloudyunx	feat(Combinatorics/SimpleGraph): Eulerian walk in connected graph contains all vertices	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-combinatorics new-contributor	16/0	Mathlib/Combinatorics/SimpleGraph/Trails.lean	1	6	['IvanRenison', 'github-actions', 'vlad902']	kmill assignee:kmill	133-76897 4 months ago	133-76897 4 months ago	0-0 0 seconds
30828	DeVilhena-Paulo author:DeVilhena-Paulo	feat: implementation of `Finmap.merge`	The main contribution of this pull request is the implementation of a `merge` function for finite maps (`Finmap`). The construction relies on the definition of a `merge` function for association lists (`AList`). There is also a side (unrelated) contribution on `Mathlib/Data/List/Permutation.lean`: the addition of a theorem about the permutation of a list with a head element (that is, a list of the form `a :: l`). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	new-contributor t-data	449/3	Mathlib/Data/Finmap.lean,Mathlib/Data/List/AList.lean,Mathlib/Data/List/Permutation.lean,Mathlib/Data/List/Sigma.lean	4	1	['github-actions']	nobody	132-13929 4 months ago	132-14008 4 months ago	132-14050 132 days
28676	sun123zxy author:sun123zxy	feat(NumberTheory/ArithmeticFunction): wrap `Nat.totient` as an `ArithmeticFunction`	This wraps the Euler's totient function `Nat.totient` into a new `ArithmeticFunction` `ϕ`, with some basic identities such as `ϕ * ζ = id` and `μ * id = ϕ.` --- We use the notation `ϕ` to distinguish from `Nat.totient`'s notation `φ`, however this might be controversial. Suggestions are welcome! [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-number-theory new-contributor large-import	45/5	Mathlib/NumberTheory/ArithmeticFunction.lean	1	19	['MichaelStollBayreuth', 'SnirBroshi', 'b-mehta', 'eric-wieser', 'github-actions', 'mathlib4-merge-conflict-bot', 'riccardobrasca', 'sun123zxy']	MichaelStollBayreuth assignee:MichaelStollBayreuth	127-46368 4 months ago	127-46368 4 months ago	53-40892 53 days
30299	franv314 author:franv314	feat(Topology/Instances): Cantor set	Prove that the Cantor set has empty interior and the cardinality of the continuum as discussed on [Zulip](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/A.20few.20results.20about.20the.20Cantor.20set/with/543560670) Moves: - Mathlib.Topology.Instances.CantorSet -> Mathlib.Topology.Instances.CantorSet.Basic --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-topology new-contributor file-removed	355/2	Mathlib.lean,Mathlib/Topology/Instances/CantorSet/Basic.lean,Mathlib/Topology/Instances/CantorSet/Cardinality.lean,Mathlib/Topology/Instances/CantorSet/Lemmas.lean	4	5	['github-actions', 'grunweg', 'kckennylau', 'mathlib4-merge-conflict-bot']	nobody	127-38098 4 months ago	127-38099 4 months ago	0-2409 40 minutes
30303	franv314 author:franv314	chore(Topology/Instances): add deprecated module	Add deprecated module to moved Cantor set file. --- - [ ] depends on: #30299 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict new-contributor	486/124	Mathlib.lean,Mathlib/Topology/Instances/CantorSet.lean,Mathlib/Topology/Instances/CantorSet/Basic.lean,Mathlib/Topology/Instances/CantorSet/Cardinality.lean,Mathlib/Topology/Instances/CantorSet/Lemmas.lean	5	3	['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	127-38096 4 months ago	127-38097 4 months ago	0-340 5 minutes
29871	zach1502 author:zach1502	feat(Matrix/Transvection): Gauss pivot determinant identity and pivot preservation	This PR adds two lemmas formalizing standard Gaussian pivot identities: * `Matrix.Transvection.listTransvecCol_mul_mul_listTransvecRow_pivot`: After applying the canonical left/right transvection products that clear the last column and row, the pivot (bottom-right) entry of a matrix is unchanged. Marked `@[simp]`. * `Matrix.Transvection.det_eq_detTopLeft_mul_pivot`: If the pivot entry is nonzero, then the determinant of the matrix factors as the determinant of the top-left block times the pivot entry, after performing the canonical transvections. This is the usual Gauss–pivot determinant identity. * Added simple usage tests in `MathlibTest/matrix.lean` to check that the new lemmas are usable by `simp`/`simpa`. --- --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-algebra new-contributor label:t-algebra$	94/0	Mathlib/LinearAlgebra/Matrix/Transvection.lean,MathlibTest/matrix.lean	2	3	['github-actions', 'riccardobrasca', 'zach1502']	nobody	121-37619 4 months ago	121-37619 4 months ago	42-32522 42 days
30158	nicolaviolette author:nicolaviolette	feat: combinatorics simplegraph basic	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-combinatorics new-contributor	9/4	Mathlib/Combinatorics/SimpleGraph/Basic.lean	1	3	['b-mehta', 'github-actions']	b-mehta assignee:b-mehta	120-57149 4 months ago	120-57149 4 months ago	31-69826 31 days
26901	5hv5hvnk author:5hv5hvnk	feat: a simproc version of `compute_degree`	Wrap `compute_degree` in a simproc for use by simp. Closes #22219. ---	awaiting-author merge-conflict t-meta awaiting-CI new-contributor	198/0	Mathlib.lean,Mathlib/Tactic/Simproc/PolynomialDegree.lean,MathlibTest/polynomial_degree_simproc.lean	3	19	['5hv5hvnk', 'YaelDillies', 'adomani', 'github-actions', 'mathlib4-merge-conflict-bot']	nobody	118-17417 3 months ago	118-17418 3 months ago	2-71043 2 days
30150	imbrem author:imbrem	feat(CategoryTheory/Monoidal): to_additive for MonoidalCategory	Add `AddMonoidalCategory`, the additive version of `MonoidalCategory`. To get this to work, I needed to _remove_ the `to_additive` attributes in `Discrete.lean`, since existing code relies on the `AddMonoid M → MonoidalCategory M` instance. For now, we simply implement the additive variants by hand instead. --- As discussed in #28718; I added an `AddMonoidalCategory` struct and tagged `MonoidalCategory` with `to_additive`, along with the lemmas in `Category.lean`. I think this is the right approach, since under this framework the "correct" additive version of `Discrete.lean` would be mapping an `AddMonoid` to an `AddMonoidalCategory`. Next steps would be to: - Make `monoidal_coherence` and `coherence` support `AddMonoidalCategory` - Add `CocartesianMonoidalCategory` extending `AddMonoidalCategory` [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-meta t-category-theory new-contributor awaiting-zulip large-import	444/125	Mathlib/CategoryTheory/Monoidal/Category.lean,Mathlib/CategoryTheory/Monoidal/Discrete.lean,Mathlib/Tactic/ToAdditive/GuessName.lean	3	22	['JovanGerb', 'YaelDillies', 'github-actions', 'imbrem', 'mathlib4-merge-conflict-bot']	nobody	111-66808 3 months ago	111-66808 3 months ago	1-18384 1 day
15651	TpmKranz author:TpmKranz	feat(Computability/NFA): operations for Thompson's construction	Lays the groundwork for a proof of equivalence of RE and NFA, w.r.t. described language. Actual connection to REs comes later, after the groundwork for the opposite direction has been laid. Third chunk of #12648 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict new-contributor t-computability awaiting-zulip	307/5	Mathlib/Computability/NFA.lean	1	27	['TpmKranz', 'YaelDillies', 'dupuisf', 'github-actions', 'leanprover-community-bot-assistant', 'meithecatte', 'rudynicolop']	nobody	106-83940 3 months ago	289-20099 9 months ago	0-0 0 seconds
15649	TpmKranz author:TpmKranz	feat(Computability): introduce Generalised NFA as bridge to Regular Expression	Lays the groundwork for a proof of equivalence of NFA and RE, w.r.t. described language. Actual connection to NFA comes later, after the groundwork for the opposite direction has been laid. Second chunk of #12648 --- - [x] depends on: #15647 [Data.FinEnum.Option unchanged since then] [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict new-contributor t-computability awaiting-zulip	298/0	Mathlib.lean,Mathlib/Computability/GNFA.lean,Mathlib/Computability/Language.lean,Mathlib/Computability/RegularExpressions.lean,docs/references.bib	5	7	['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'meithecatte', 'trivial1711']	nobody	106-13781 3 months ago	106-13782 3 months ago	0-0 0 seconds
5919	MithicSpirit author:MithicSpirit	feat: implement orthogonality for AffineSubspace	Define `AffineSubspace.orthogonal` and `AffineSubspace.IsOrtho`, as well as develop an API emulating that of `Submodule.orthogonal` and `Submodule.IsOrtho`, respectively. Additionally, provide some relevant lemmas exclusive to affine subspaces, which are mostly to do with the relationship between orthogonality and `AffineSubspace.Parallel`. Closes #5539 --- Still WIP as I need to add more docstrings as well as notations for the new definitions. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted WIP merge-conflict t-analysis new-contributor	287/0	Mathlib.lean,Mathlib/Analysis/InnerProductSpace/AffineSubspace.lean	2	7	['MithicSpirit', 'eric-wieser', 'github-actions', 'leanprover-community-bot-assistant', 'mathlib4-merge-conflict-bot']	MithicSpirit assignee:MithicSpirit	105-51638 3 months ago	105-51638 3 months ago	0-0 0 seconds
13442	dignissimus author:dignissimus	feat: mabel tactic for multiplicative abelian groups	Mabel tactic for multiplicative abelian groups (#10361) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	help-wanted awaiting-author modifies-tactic-syntax merge-conflict t-meta new-contributor	439/0	Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/MAbel.lean,MathlibTest/mabel.lean	4	11	['BoltonBailey', 'dignissimus', 'github-actions', 'joneugster', 'kbuzzard', 'mathlib4-merge-conflict-bot']	joneugster assignee:joneugster	105-51374 3 months ago	105-51375 3 months ago	0-0 0 seconds
14237	js2357 author:js2357	feat: Define the localization of a fractional ideal at a prime ideal	Define the localization of a fractional ideal at a prime ideal, and prove some basic properties. --- This PR is part 3 out of 4 of a proof of `isDedekindDomain_iff_isDedekindDomainDvr`. Part 4 is available here: #14242 - [x] depends on: #14099 Part 1 - [x] depends on: #14216 Part 2 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-algebra new-contributor label:t-algebra$	230/0	Mathlib.lean,Mathlib/RingTheory/FractionalIdeal/LocalizedAtPrime.lean,Mathlib/RingTheory/Localization/Basic.lean	3	22	['Vierkantor', 'YaelDillies', 'github-actions', 'js2357', 'kbuzzard', 'leanprover-community-bot-assistant', 'leanprover-community-mathlib4-bot', 'mathlib4-merge-conflict-bot']	Vierkantor assignee:Vierkantor	105-51372 3 months ago	105-51373 3 months ago	0-0 0 seconds
15224	AnthonyBordg author:AnthonyBordg	feat(CategoryTheory/Sites): covering families and their associated Grothendieck topology	Define covering families on a category and their associated Grothendieck topology by using the API for `Coverage`. Give an explicit characterization of the covering sieves of the said topology. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-category-theory new-contributor	112/0	Mathlib.lean,Mathlib/CategoryTheory/Sites/CoveringFamilies.lean	2	21	['AnthonyBordg', 'adamtopaz', 'dagurtomas', 'github-actions', 'joelriou', 'mathlib4-merge-conflict-bot']	nobody	105-51243 3 months ago	105-51244 3 months ago	0-0 0 seconds
20648	anthonyde author:anthonyde	feat: formalize regular expression -> εNFA	The file `Computability/RegularExpressionsToEpsilonNFA.lean` contains a formal definition of Thompson's method for constructing an `εNFA` from a `RegularExpression` and a proof of its correctness. --- - [x] depends on: #20644 - [x] depends on: #20645 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor t-computability awaiting-zulip	490/0	Mathlib.lean,Mathlib/Computability/RegularExpressionsToEpsilonNFA.lean,docs/references.bib	3	7	['anthonyde', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'meithecatte', 'qawbecrdtey']	nobody	105-50949 3 months ago	105-50950 3 months ago	0-0 0 seconds
21903	yhtq author:yhtq	feat: add from/toList between `FreeSemigroup` and `List` with relative theorems	Add from/toList between `FreeSemigroup` and `List` with relative theorems, as well as an incidental definition of lexicographic order on `FreeSemigroup`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict awaiting-CI t-algebra new-contributor large-import label:t-algebra$	169/0	Mathlib/Algebra/Free.lean	1	12	['YaelDillies', 'github-actions', 'mathlib4-merge-conflict-bot']	nobody	105-50809 3 months ago	105-50810 3 months ago	0-0 0 seconds
22159	shetzl author:shetzl	feat: add definition of pushdown automata	Add the definition of pushdown automata and their two acceptance conditions: acceptance based on empty stack and acceptance based on final state. Co-authored-by: Tobias Leichtfried --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict new-contributor t-computability	70/0	Mathlib.lean,Mathlib/Computability/PDA.lean	2	35	['YaelDillies', 'github-actions', 'madvorak', 'mathlib4-merge-conflict-bot', 'shetzl']	nobody	105-50803 3 months ago	105-50804 3 months ago	0-0 0 seconds
22302	658060 author:658060	feat: add `CategoryTheory.Topos.Power`	This is a continuation of #21281 with the end goal of defining topoi in Mathlib. It introduces the notion of a power object in a category with a subobject classifier, which is a special case of an internal hom. The definition `HasPowerObjects C` contained in this PR is all that remains before `IsTopos C` can be defined. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-category-theory new-contributor	312/0	Mathlib.lean,Mathlib/CategoryTheory/Topos/Power.lean	2	3	['github-actions', 'joelriou', 'mathlib4-merge-conflict-bot']	b-mehta assignee:b-mehta	105-50794 3 months ago	105-50795 3 months ago	0-0 0 seconds
22314	shetzl author:shetzl	feat: add leftmost derivations for context-free grammars	Leftmost derivations are often easier to reason about than arbitrary derivations. This PR adds leftmost variants of Rewrites, Produces and Derives to the existing definition of context-free grammars and proves that a string of terminals can be derived iff it can be leftmost derived. Co-authored-by: Tobias Leichtfried --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict new-contributor t-computability	383/0	Mathlib.lean,Mathlib/Computability/LeftmostDerivation.lean	2	55	['YaelDillies', 'github-actions', 'madvorak', 'mathlib4-merge-conflict-bot', 'shetzl']	YaelDillies assignee:YaelDillies	105-50792 3 months ago	105-50793 3 months ago	0-0 0 seconds
22790	mhk119 author:mhk119	feat: Extend `taylor_mean_remainder_lagrange` to `x < x_0`	The `taylor_mean_remainder_lagrange` theorem has the assumption that $x_0 < x$. In many applications, we need $x < x_0$ and one cannot use the current version to obtain this (see [zulip](https://leanprover.zulipchat.com/#narrow/channel/116395-maths/topic/Taylor's.20theorem)). This PR introduces a set of theorems that push negations through Taylor expansions so that one can extend `taylor_mean_remainder_lagrange` to the case when $x < x_0$. These theorems should also be useful elsewhere since they are quite general.	awaiting-author merge-conflict t-analysis new-contributor	111/1	Mathlib/Analysis/Calculus/Deriv/Basic.lean,Mathlib/Analysis/Calculus/IteratedDeriv/Lemmas.lean,Mathlib/Analysis/Calculus/Taylor.lean	3	13	['Paul-Lez', 'github-actions', 'grunweg', 'mathlib4-merge-conflict-bot', 'mhk119']	nobody	105-50781 3 months ago	105-50782 3 months ago	0-0 0 seconds
24333	xcloudyunx author:xcloudyunx	feat(Combinatorics/SimpleGraph): cycle graph implementation for generic vertex types	The existing `cycleGraph` implementation under Combinatorics/SimpleGraph/Circulant.lean only operates over `Fin n`. This PR implements a cycle graph implementation over any generic vertex type. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-combinatorics new-contributor	187/0	Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Cycle.lean	2	42	['IvanRenison', 'github-actions', 'mathlib4-merge-conflict-bot', 'vlad902']	kmill assignee:kmill	105-50628 3 months ago	105-50629 3 months ago	0-0 0 seconds
25739	literandltx author:literandltx	feat(NumberTheory/LegendreSymbol): Add sqrt‐of‐residue theorems for p=4k+3 and p=8k+5	Add a new file `QuadraticResidueRoots.lean` under `Mathlib/NumberTheory/LegendreSymbol/` that proves two explicit “square-root of quadratic residue” theorems for primes of the specific form. - `exists_sqrt_of_residue_mod4_eq3` for primes `p = 4k + 3` - `exists_sqrt_of_residue_mod8_eq5`* for primes `p = 8*k + 5` It also introduces the helper lemmas `euler_criterion_traditional` and `legendreSym.at_two_mod8_eq_5`. Import lines in `Mathlib.lean` and `Mathlib/NumberTheory/LegendreSymbol/Basic.lean` have been updated accordingly.	awaiting-author merge-conflict t-number-theory new-contributor	217/0	Mathlib.lean,Mathlib/NumberTheory/LegendreSymbol/Basic.lean,Mathlib/NumberTheory/LegendreSymbol/QuadraticReciprocity.lean,Mathlib/NumberTheory/LegendreSymbol/QuadraticResidueRoots.lean	4	3	['github-actions', 'kckennylau', 'mathlib4-merge-conflict-bot']	literandltx assignee:literandltx	105-50479 3 months ago	105-50480 3 months ago	17-63153 17 days
26165	oliver-butterley author:oliver-butterley	feat(MeasureTheory.VectorMeasure): add lemma which shows that variation of a `ℝ≥0∞` VectorMeasure is equal to itself	Add a lemma for the variation of a VectorMeasure which tells that if `μ` is `VectorMeasure X ℝ≥0∞` then `variation μ = μ`. Co-authored-by: @yoh-tanimoto - [ ] depends on: #26160 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-measure-probability new-contributor	467/0	Mathlib.lean,Mathlib/MeasureTheory/VectorMeasure/Variation/Defs.lean,Mathlib/MeasureTheory/VectorMeasure/Variation/Lemmas.lean	3	3	['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	105-50290 3 months ago	105-50291 3 months ago	15-66224 15 days
26300	igorkhavkine author:igorkhavkine	feat(Analysis/Calculus/FDeriv): continuous differentiability from continuous partial derivatives on an open domain in a product space	If a function `f : E × F → G` is continuously differentiable, then its partial derivatives along `E` and `F` are also continuous. The non-trivial converse implication holds when the partial derivatives are continuous on an open domain, and they can be added together to give the total derivative of `f`. See this [#mathlib4 > Partial derivatives @ 💬](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Partial.20derivatives/near/520995477) and the containing thread for some discussion. The PR creates a new import (`Mathlib.Analysis.Calculus.FDeriv.Partial`), where other results about partial derivatives could go in the future. --- this is the migration of #25304 to the PR-from-fork workflow - [x] depends on: #25564 - [x] depends on: #26273 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP awaiting-author merge-conflict t-analysis new-contributor	468/0	Mathlib.lean,Mathlib/Analysis/Calculus/FDeriv/Partial.lean,Mathlib/Analysis/Normed/Operator/BoundedLinearMaps.lean	3	21	['YaelDillies', 'agjftucker', 'github-actions', 'igorkhavkine', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'sgouezel']	sgouezel assignee:sgouezel	105-50267 3 months ago	105-50268 3 months ago	50-22679 50 days
26594	metakunt author:metakunt	feat(Algebra/Polynomial/ZMod): Add Polynomial.equiv_of_nat_of_polynomial_zmod	This adds an explicit bijection between the naturals and $$\mathbb{Z}/n\mathbb{Z}[X]$$ in a canonical way. --- I feel that some API is missing to make the theorem shorter, I have no idea what lemmas to extract though. Also I don't know when to use spaces and when not, so I did it best effort.	awaiting-author merge-conflict t-algebra new-contributor label:t-algebra$	465/0	Mathlib.lean,Mathlib/Algebra/Polynomial/ZMod.lean	2	3	['Ruben-VandeVelde', 'github-actions', 'mathlib4-merge-conflict-bot']	nobody	105-50119 3 months ago	105-50120 3 months ago	25-6199 25 days
26757	fweth author:fweth	feat(CategoryTheory/Topos): define elementary topos	This commit begins the formalization of the notion of an elementary topos, following the definition in \[Mac Lane & Moerdijk, Sheaves in Geometry and Logic (1992), Ch. IV, Section 1]. It introduces the file `Mathlib/CategoryTheory/Topos/Basic.lean`, which currently includes: * The definition of an elementary topos. * Proof that the power object map is a functor * Theorem about pullbacks of characterstic maps Subobject classifiers, which are used in the definition, have already been defined in `CategoryTheory/Topos/Classifier.lean` Work in progress: further formalization of the section is planned. Questions: * Should the definition of power objects be separated into its own file/module, perhaps under `CategoryTheory/Topos/PowerObject.lean`? * Is the notation `P` / `P_morph` / `P_functor` for the power object functor on objects / morphisms / total acceptable? * Should the comments and docstrings rather use the notation from the book, where `g ∘ f` denotes arrow composition from righ to left, or the Lean variant `f ≫ g`? Klaus Gy klausgy@gmail.com --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-category-theory new-contributor	401/66	Mathlib.lean,Mathlib/CategoryTheory/Closed/PowerObjects.lean,Mathlib/CategoryTheory/Limits/Shapes/BinaryProducts.lean,Mathlib/CategoryTheory/Limits/Shapes/Equalizers.lean,Mathlib/CategoryTheory/Limits/Shapes/Pullback/CommSq.lean,Mathlib/CategoryTheory/Limits/Shapes/Pullback/Equalizer.lean,Mathlib/CategoryTheory/Monoidal/Cartesian/Basic.lean,Mathlib/CategoryTheory/Subobject/Basic.lean,Mathlib/CategoryTheory/Topos/Classifier.lean	9	17	['fweth', 'github-actions', 'joelriou', 'leanprover-community-bot-assistant', 'mathlib4-merge-conflict-bot']	joelriou assignee:joelriou	105-50114 3 months ago	105-50115 3 months ago	62-83085 62 days
27155	Pjotr5 author:Pjotr5	feat: Shearer's bound on the independence number of triangle free graphs	I added the file IndependenceNumber.lean to the Mathlib.Combinatorics.SimpleGraph.Triangle folder. It contains a proof of a theorem by Shearer on the independence number of triangle-free graphs . I was told this might be useful to add to Mathlib a Zullip thread linked [here](https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/Convexity.20of.20a.20specific.20function/with/510469526). I tried to comply as much as I could with the Mathlib style guide, but I realise that there is probably still a significant amount of editing to be done. For one thing: there are probably some lemmas and theorems in there that might be better suited in other files, but since this is my first PR I though I would all put it in one file before starting to edit a bunch of files. I was also advised to split up the file into multiple smaller PRs, but since everything is basically serving this one proof I could not really find a natural way to do that. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-combinatorics new-contributor	1266/0	Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Triangle/IndependenceNumber.lean	2	10	['Pjotr5', 'github-actions', 'grunweg', 'mathlib4-merge-conflict-bot']	nobody	105-50077 3 months ago	105-50078 3 months ago	39-17587 39 days
27753	YunkaiZhang233 author:YunkaiZhang233	feat(CategoryTheory): implemented proofs for factorisation categories being equivalent to iterated comma categories in two ways	--- Completed one of the tasks in TODOs, shown and implemented the details for (X/C)/f ≌ Factorisation f ≌ f/(C/Y). This is migrated from my previous PR #22390 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-category-theory new-contributor	70/1	Mathlib/CategoryTheory/Category/Factorisation.lean	1	13	['YunkaiZhang233', 'b-mehta', 'github-actions', 'mathlib4-merge-conflict-bot', 'robin-carlier']	nobody	105-49922 3 months ago	105-49923 3 months ago	0-3448 57 minutes
27850	fyqing author:fyqing	feat: 0-dimensional manifolds are discrete and countable	This is the converse direction of the classification of 0-dimensional manifolds. The other direction was shown in #22105. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-differential-geometry new-contributor	80/0	Mathlib.lean,Mathlib/Geometry/Manifold/ZeroDim.lean	2	14	['fyqing', 'github-actions', 'grunweg', 'mathlib4-merge-conflict-bot', 'tb65536']	grunweg assignee:grunweg	105-49920 3 months ago	105-49921 3 months ago	0-6418 1 hour
28125	nonisomorphiclinearmap author:nonisomorphiclinearmap	feat(Combinatorics): basic definition of simplicial complexes	This PR introduces the basic definition of a finite (abstract) simplicial complex, located in Mathlib/Combinatorics/SimplicialComplex/Basic.lean. --- This is our first contribution to mathlib. This work was done as part of the Fields Institute Summer Undergraduate Program on formalization in topological combinatorics. Eventually, we aim to formalize Lovasz's proof of the Kneser Conjecture and this is a small stepping stone in that direction. Some other commits will shortly depend on this one. We would like to acknowledge the Fields Institute for Research in Mathematical Sciences for their sponsorship. We would also like to thank our supervisors, Professor Chris Kapulkin and Mr. Daniel Carranza, for their guidance and support throughout this project. We would also like to thank our group members Tom Lindquist and Quang Minh Nguyen for our fruitful discussions.	merge-conflict t-combinatorics new-contributor	374/0	Mathlib.lean,Mathlib/Combinatorics/SimplicialComplex/Basic.lean,Mathlib/Combinatorics/SimplicialComplex/Category.lean,Mathlib/Combinatorics/SimplicialComplex/FacePoset.lean,Mathlib/Combinatorics/SimplicialComplex/Hom.lean	5	2	['github-actions', 'mathlib4-merge-conflict-bot']	awainverse assignee:awainverse	105-49788 3 months ago	105-49789 3 months ago	102-43516 102 days
28530	nonisomorphiclinearmap author:nonisomorphiclinearmap	feat(Combinatorics/SimplicialComplex/Topology): add standard simplices and geometric realisation (colimit + functoriality)	Introduce the standard simplex on a finite vertex set and build the geometric realisation \|X\| of a simplicial complex. Prove that \|X\| is the colimit of the face diagram δ_X : X.faces ⥤ TopCat, and define the induced map on realisations \|φ\| : \|X\| ⟶ \|Y\| for a simplicial map φ. Show that the abstract map from colimit functoriality agrees with the concrete push-forward of barycentric coordinates. Package these into a functor SimplicialComplexCat ⥤ TopCat. --- This is our first contribution to mathlib. This work was done as part of the Fields Institute Summer Undergraduate Program on formalization in topological combinatorics. Eventually, we aim to formalize Lovasz's proof of the Kneser Conjecture and this lays the groundwork to do this. We would like to acknowledge the Fields Institute for Research in Mathematical Sciences for their sponsorship. We would also like to thank our supervisors, Professor Chris Kapulkin and Mr. Daniel Carranza, for their guidance and support throughout this project. I would also like to thank our group members Sebastian Kumar, Tom Lindquist and Quang Minh Nguyen for our fruitful discussions. - [ ] depends on: #28125	blocked-by-other-PR merge-conflict t-combinatorics new-contributor	1826/0	Mathlib.lean,Mathlib/Combinatorics/SimplicialComplex/Basic.lean,Mathlib/Combinatorics/SimplicialComplex/Category.lean,Mathlib/Combinatorics/SimplicialComplex/FacePoset.lean,Mathlib/Combinatorics/SimplicialComplex/Hom.lean,Mathlib/Combinatorics/SimplicialComplex/Topology/GeomReal/Basic.lean,Mathlib/Combinatorics/SimplicialComplex/Topology/GeomReal/Colimit.lean,Mathlib/Combinatorics/SimplicialComplex/Topology/GeomReal/Diagram.lean,Mathlib/Combinatorics/SimplicialComplex/Topology/GeomReal/Functor.lean,Mathlib/Combinatorics/SimplicialComplex/Topology/GeomReal/Map.lean,Mathlib/Combinatorics/SimplicialComplex/Topology/Simplex.lean,Mathlib/Combinatorics/SimplicialComplex/Topology/SimplexMap.lean	12	3	['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	105-49774 3 months ago	105-49774 3 months ago	0-591 9 minutes
28871	JaafarTanoukhi author:JaafarTanoukhi	feat(Combinatorics/Digraph): Tournaments	Define orientations and tournaments. Related to #26771. Co-authored-by: Rida Hamadani --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-combinatorics new-contributor	62/0	Mathlib.lean,Mathlib/Combinatorics/Digraph/Orientation.lean,Mathlib/Combinatorics/Digraph/Tournament.lean	3	6	['JaafarTanoukhi', 'Rida-Hamadani', 'SnirBroshi', 'github-actions', 'mathlib4-merge-conflict-bot']	kmill assignee:kmill	105-49635 3 months ago	105-49636 3 months ago	86-45080 86 days
29947	JaafarTanoukhi author:JaafarTanoukhi	feat(Combinatorics/Digraph): Maps	Ported `SimpleGraph/Maps.lean` to `Digraph/Maps.lean` for future PRs related to issue #[26771](https://github.com/leanprover-community/mathlib4/issues/26771) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-combinatorics new-contributor	476/0	Mathlib.lean,Mathlib/Combinatorics/Digraph/Maps.lean	2	2	['github-actions', 'mathlib4-merge-conflict-bot']	awainverse assignee:awainverse	105-49001 3 months ago	105-49002 3 months ago	55-55764 55 days
31590	SuccessMoses author:SuccessMoses	chore: tag `commutatorElement_def` with `simp`	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-algebra new-contributor label:t-algebra$	1/0	Mathlib/Algebra/Group/Commutator.lean	1	2	['github-actions', 'grunweg']	nobody	105-23708 3 months ago	105-23708 3 months ago	6-8213 6 days
11021	jstoobysmith author:jstoobysmith	feat(AlgebraicTopology): add join of augmented SSets	This pull-request adds the definition of the join of augmented SSets defined as contravariant functors from `WithInitial SimplexCategory` to `Type u`. In addition it shows that the join of two standard augmented SSets is again an augmented SSets. From this the definition of the join of simplicial sets should follow easily. To aid the above theory, an api for `WithInitial SimplexCategory` has been created, with the notion of the `join` and `split` (forming a sort of inverse to join) of objects in this category are defined. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP merge-conflict new-contributor t-algebraic-topology	2137/1	.gitignore,Mathlib.lean,Mathlib/AlgebraicTopology/Join.lean,Mathlib/AlgebraicTopology/SimplexCategory.lean,Mathlib/AlgebraicTopology/SimplexCategoryWithInitial.lean,Mathlib/AlgebraicTopology/SimplicialSet.lean	6	47	['github-actions', 'jcommelin']	nobody	105-22849 3 months ago	216-35263 7 months ago	0-0 0 seconds
18626	hannahfechtner author:hannahfechtner	feat: define Artin braid groups	Define the Artin braid group on infinitely many strands. Includes a toGroup function which defines a function out of the braid group to any other group (given a function which satisfies the braid relations) (more to come in this file; next up: Artin braid groups on finitely many strands) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-algebra new-contributor label:t-algebra$	91/0	Mathlib.lean,Mathlib/GroupTheory/SpecificGroups/BraidGroup/Basic.lean	2	22	['github-actions', 'hannahfechtner', 'jcommelin', 'joelriou']	nobody	105-22696 3 months ago	368-20211 1 year ago	0-0 0 seconds
20029	FrederickPu author:FrederickPu	feat(Tactic/simps): allow for Config attributes to be set directly	Allow for Config attributes to be set directly when using initialize_simp_projection as per issue #19895 Basically modified initialize_simp_projection so that the user has the option of specifying a tuple of config option values. Ex: ``` initialize_simp_projection MulEquiv (toFun → apply, invFun → symm_apply) (fullyApplied := false) ``` These config options are then converted into projections. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP merge-conflict t-meta new-contributor	34/4	Mathlib/Tactic/Simps/Basic.lean	1	11	['FrederickPu', 'YaelDillies', 'fpvandoorn', 'github-actions', 'leanprover-community-bot-assistant']	nobody	105-22633 3 months ago	222-4105 7 months ago	0-0 0 seconds
21269	658060 author:658060	feat(CategoryTheory/Topos): basic definitions and results in topos theory	This code contains basic definitions and results in topos theory, including the definition of a subobject classifier, power objects, and topoi. It is proved that every topos has exponential objects, i.e. "internal homs". The mathematical content follows chapter IV sections 1-2 of Mac Lane and Moerdijk's text "Sheaves in Geometry and Logic". --- - [x] depends on: #21281 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP awaiting-author merge-conflict t-category-theory new-contributor	1269/0	Mathlib.lean,Mathlib/CategoryTheory/Topos/Basic.lean,Mathlib/CategoryTheory/Topos/Classifier.lean,Mathlib/CategoryTheory/Topos/Exponentials.lean,Mathlib/CategoryTheory/Topos/Power.lean	5	10	['658060', 'gio256', 'github-actions', 'joelriou', 'mathlib4-dependent-issues-bot']	nobody	105-22606 3 months ago	372-79974 1 year ago	0-0 0 seconds
23990	robertmaxton42 author:robertmaxton42	feat(Types.Colimits): Quot is functorial and colimitEquivQuot is natural	Add `Functor.quotFunctor` to parallel `Functor.sectionsFunctor`, witnessing that `Quot` is functorial; add `colimNatIsoQuotFunctor` to parallel `limNatIsoSectionsFunctor`, witnessing that `colimitEquivQuot` is natural in the diagram $F$. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-category-theory new-contributor	33/0	Mathlib/CategoryTheory/Limits/Types/Colimits.lean	1	5	['github-actions', 'joelriou', 'leanprover-community-bot-assistant', 'robertmaxton42']	nobody	105-22489 3 months ago	238-70892 7 months ago	0-0 0 seconds
26881	emo916math author:emo916math	feat(Analysis/Calculus/Deriv/Star): a formula for `deriv (conj ∘ f ∘ conj)`	Added a lemma that `deriv (conj ∘ f ∘ conj) = conj ∘ deriv f ∘ conj`, proved by cases on whether the derivative mathematically exists or not. This PR replaces [#26805](https://github.com/leanprover-community/mathlib4/pull/26805); see discussion there. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-analysis new-contributor	50/2	Mathlib/Analysis/Calculus/Deriv/Star.lean	1	15	['emo916math', 'github-actions', 'j-loreaux', 'kckennylau']	j-loreaux assignee:j-loreaux	105-22255 3 months ago	208-22003 6 months ago	31-70575 31 days
27991	sinianluoye author:sinianluoye	feat(Rat): add Rat.den_eq_of_add_den_eq_one and its dependent lemmas	```lean4 example {q r : ℚ} (h : (q + r).den = 1) : q.den = r.den := by ``` It is so simple, but I couldn't find it in current mathlib repo. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author new-contributor t-data	22/0	Mathlib/Data/Rat/Lemmas.lean	1	33	['github-actions', 'kim-em', 'mathlib-bors', 'pechersky', 'sinianluoye', 'themathqueen']	pechersky assignee:pechersky	105-22172 3 months ago	128-67634 4 months ago	80-3629 80 days
28215	5hv5hvnk author:5hv5hvnk	feat: strong and Weak connectivity for Digraphs	strong and weak connectivity in Digraphs --- Should resolve a part of issue #26771 Main additions in the PR: 1. Walks in Digraphs (Walk.lean) - Basic walk structure with start and end vertices - Support for walk operations: append, reverse, length - Support functions: getVert, copy, support 2. Walk Decompositions (WalkDecomp.lean) - takeUntil and dropUntil functions to split walks - rotate operation for loop walks - Theorems relating to walk decomposition properties 3. Subgraphs (subgraph.lean) - Subgraph structure for digraphs - Induced and spanning subgraph predicates - Lattice structure (sup, inf, top, bot) - Coercion to standalone digraphs 4. Paths (Paths.lean) - Trail, Path, Circuit, Cycle definitions - Path structure with no repeating vertices - Theorems relating different path types - Basic connectivity definitions (reachable, weakly/strongly connected) 5. Connectivity (Connected.lean) - Reachability relations and properties - Strong and weak connectivity definitions - Connected component types: - StronglyConnectedComponent - WeaklyConnectedComponent - ConnectedComponent - Component properties and equivalence relations --> [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP awaiting-author merge-conflict t-combinatorics new-contributor	1266/0	Mathlib.lean,Mathlib/Combinatorics/Digraph/Connected.lean,Mathlib/Combinatorics/Digraph/Paths.lean,Mathlib/Combinatorics/Digraph/Subgraph.lean,Mathlib/Combinatorics/Digraph/Walk.lean,Mathlib/Combinatorics/Digraph/WalkDecomp.lean	6	4	['github-actions', 'grunweg', 'mathlib4-merge-conflict-bot']	nobody	105-22151 3 months ago	105-22151 3 months ago	12-41939 12 days
29574	JarodAlper author:JarodAlper	feat: regular local rings are domains	We have added three new files in Mathlib/RingTheory/LocalRing * EmbeddingDimension.lean * LocalRingDimension.lean * RegularLocalRings.lean We have added two lemmas and an instance in Mathlib/RingTheory/LocalRing/RingHom/Basic.lean This work was done by Jarod Alper and Brian Nugent. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor t-ring-theory	910/3	Mathlib.lean,Mathlib/RingTheory/LocalRing/EmbeddingDimension.lean,Mathlib/RingTheory/LocalRing/LocalRingDimension.lean,Mathlib/RingTheory/LocalRing/RegularLocalRings.lean,Mathlib/RingTheory/LocalRing/RingHom/Basic.lean,lake-manifest.json	6	2	['github-actions', 'mathlib4-merge-conflict-bot']	nobody	105-22040 3 months ago	170-65770 5 months ago	3-7974 3 days
28718	imbrem author:imbrem	feat: class for chosen finite coproducts	Added basic `ChosenFiniteCoproducts` class, and started porting some of the lemmas about `ChosenFiniteProducts` suitably translated --- This, combined with #20182 modified to use chosen finite coproducts and premonoidal categories (#21488), should be enough for me to formalize strong Elgot categories, and hence a lot of categorical iteration theory for my PhD thesis. Re-done from #21603 to deal with changes in #24399 and #24390 Eventually, if we really want to harmonize approaches, we could introduce an `AddMonoidalCategory` struct and do the analogous to #24399 and #24390 for additive monoidal structure, but that seems like a massive overcomplication for now. It would allow formalizing fun things like rig categories, though. - [ ] depends on: #30150	blocked-by-other-PR awaiting-author merge-conflict t-category-theory new-contributor	290/0	Mathlib.lean,Mathlib/CategoryTheory/ChosenFiniteCoproducts.lean	2	9	['YaelDillies', 'github-actions', 'imbrem', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'robin-carlier']	nobody	105-21952 3 months ago	105-49767 3 months ago	0-24930 6 hours
26765	KiringYJ author:KiringYJ	feat(MeasureTheory/PiSystem): add π-λ theorem and SetLike instance	Add two small features to `MeasureTheory/PiSystem`: 1. SetLike instance `instance : SetLike (DynkinSystem α) (Set α)` This lets us write `s ⊆ d` and `t ∈ d` for a DynkinSystem `d`, matching usual mathlib style. 2. `DynkinSystem.pi_lambda` lemma Classical π‑λ theorem: if a π‑system `s` is contained in a Dynkin system `d`, every set measurable for `σ(s)` is also in `d`. Currently, mathlib exposes this result only indirectly (e.g. via `generateFrom_eq`). Although logically equivalent, it is not obvious at first glance that those lemmas are the π‑λ theorem. The new lemma states the result in its familiar textbook form, so users can recognise and cite it immediately. Both pieces are under 10 lines, term‑mode only, and do not modify existing APIs. No breaking changes. No dependencies.	awaiting-author t-measure-probability new-contributor	13/0	Mathlib/MeasureTheory/PiSystem.lean	1	14	['EtienneC30', 'KiringYJ', 'dagurtomas', 'github-actions', 'ocfnash']	RemyDegenne assignee:RemyDegenne	105-8348 3 months ago	105-8348 3 months ago	138-3922 138 days
29434	ntapiam author:ntapiam	feat(NonAssoc/LieAdmissible): prove every ring/algebra is LieAdmissible	-awaiting-author	t-algebra new-contributor label:t-algebra$	27/6	Mathlib/Algebra/NonAssoc/LieAdmissible/Defs.lean	1	2	['github-actions', 'mathlib4-merge-conflict-bot']	nobody	103-6658 3 months ago	103-26031 3 months ago	175-19528 175 days
30637	strihanje01 author:strihanje01	feat(Combinatorics/SetFamily/Lindstrom): Lindstrom's theorem for subfamilies with equal unions	add Lindstrom's theorem and its strengthening for equal intersections --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-combinatorics new-contributor	209/0	Mathlib/Combinatorics/SetFamily/Lindstrom.lean	1	2	['github-actions', 'mathlib4-merge-conflict-bot']	b-mehta assignee:b-mehta	102-30497 3 months ago	103-12928 3 months ago	135-66332 135 days
31796	dobronx1325 author:dobronx1325	feat(Data/Real/EReal): add mul_lt_mul_of_pos_left theorem	This PR adds the theorem `EReal.mul_lt_mul_of_pos_left`, which states that for a positive real number `a` and extended reals `b < c`, left multiplication by `a` preserves the strict order: `(a : EReal) * b < (a : EReal) * c`. The theorem complements existing order-preserving properties for addition in `EReal` and extends the algebraic structure for multiplication. The proof uses basic properties of extended reals and order relations. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	new-contributor t-data	23/0	Mathlib/Data/EReal/Operations.lean	1	4	['JovanGerb', 'LLaurance', 'dobronx1325', 'github-actions']	nobody	98-64539 3 months ago	105-59262 3 months ago	105-59296 105 days
32169	saodimao20 author:saodimao20	feat: add convolution_comp_add_right	This PR adds a lemma `convolution_comp_translation_right` showing that convolution commutes with translation on the right operand. Specifically, it proves that for an additive commutative group $G$, the convolution of a function $f$ with a translated function $x \mapsto g(a + x)$ is equal to the convolution of $f$ and $g$ evaluated at $x + a$. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-analysis new-contributor	14/0	Mathlib/Analysis/Convolution.lean	1	3	['github-actions', 'urkud']	nobody	96-50919 3 months ago	96-50919 3 months ago	0-82278 22 hours
31898	ntapiam author:ntapiam	feat(LinearAlgebra/TensorAlgebra): implement HopfAlgebra for TensorAlgebra	implementation of the natural Hopf algebra structure on the TensorAlgebra	awaiting-author new-contributor t-ring-theory	253/0	Mathlib.lean,Mathlib/Algebra/FreeAlgebra.lean,Mathlib/LinearAlgebra/TensorAlgebra/Basic.lean,Mathlib/RingTheory/Bialgebra/FreeAlgebra.lean,Mathlib/RingTheory/Bialgebra/TensorAlgebra.lean,Mathlib/RingTheory/HopfAlgebra/TensorAlgebra.lean	6	64	['YaelDillies', 'github-actions', 'kckennylau', 'ntapiam']	nobody	89-22896 2 months ago	101-76109 3 months ago	0-63895 17 hours
30525	515801431 author:515801431	feat(Mathlib/Combinatorics/Enumerative/Polya): Add Polya Counting	This PR introduces basic definitions and results about colorings under permutation group actions. A coloring is defined as a function X → Y, and the permutation group Equiv.Perm X acts on colorings by precomposition: (g • c) x = c (g⁻¹ • x) This formalizes the natural action of relabeling the elements of X. Main definitions MulAction (Equiv.Perm X) (X → Y): The action of the permutation group on colorings via precomposition. coloringEquiv (c₁ c₂ : X → Y) : Prop: Two colorings are equivalent if they lie in the same orbit under this action, i.e. ∃ f : Equiv.Perm X, f • c₁ = c₂. Main results smul_eq_iff_mem_stabilizer: Characterizes when two group actions on the same coloring are equal, showing that g • c = f • c ↔ f⁻¹ * g ∈ stabilizer c. coloringEquiv_equivalence: Proves that coloringEquiv defines an equivalence relation on X → Y. orbit_size_eq_index: Reformulates the orbit–stabilizer theorem in the context of colorings: \|orbit c\| = \|Perm X\| / \|stabilizer c\| Motivation These results provide foundational infrastructure for studying Burnside’s lemma and Pólya’s enumeration theorem in Mathlib, where the enumeration of distinct colorings up to symmetry plays a central role.	awaiting-author merge-conflict t-combinatorics new-contributor	113/0	Mathlib.lean,Mathlib/Combinatorics/Enumerative/Polya.lean	2	8	['IvanRenison', 'alreadydone', 'github-actions', 'mathlib4-merge-conflict-bot']	awainverse assignee:awainverse	89-9658 2 months ago	89-9658 2 months ago	40-50241 40 days
31113	515801431 author:515801431	feat(Mathlib/Combinatorics/Enumerative/Polya.lean): Add additional theorem in `Polya.lean`	--- - [ ] depends on: #30525 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-combinatorics new-contributor	302/0	Mathlib.lean,Mathlib/Combinatorics/Enumerative/Polya.lean	2	4	['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	b-mehta assignee:b-mehta	89-9534 2 months ago	89-9535 2 months ago	22-58765 22 days
24441	MrSumato author:MrSumato	feat(Data/List): add Lyndon-Schutzenberger theorem on list commutativity	Add Lyndon-Schutzenberger theorem on list commutativity. Included definition for List.repeatSelf that returns list repeated n times. --- This is my first mathlib PR, so any comments are highly appreciated. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict new-contributor t-data	129/1	Mathlib.lean,Mathlib/Data/List/Commutativity.lean,Mathlib/Data/List/Defs.lean,Mathlib/Data/List/Lemmas.lean	4	38	['MrSumato', 'github-actions', 'grunweg', 'madvorak', 'mathlib4-merge-conflict-bot', 'plp127']	grunweg assignee:grunweg	89-5136 2 months ago	105-50626 3 months ago	0-0 0 seconds
29744	espottesmith author:espottesmith	feat(Combinatorics): define directed hypergraphs	This PR defines directed hypergraphs: ``` @[ext] structure DiHypergraph (α : Type*) where /-- The vertex set -/ vertexSet : Set α /-- The edge set -/ edgeSet : Set ((Set α) × (Set α)) /-- Each edge is a pair (s, d), where s ⊆ vertexSet and d ⊆ vertexSet -/ edge_src_dst_isSubset_vertexSet' : ∀ ⦃e⦄, e ∈ edgeSet → e.1 ⊆ vertexSet ∧ e.2 ⊆ vertexSet ``` Additional definitions: - tail/head stars and negative/positive stars - some special cases (B-Graph, F-Graph, BF-Graph, and what I'm calling a "non-endless" dihypergraph, where neither the source/tail nor the destination/head are empty) - Vertex and (hyper)edge adjacency - isolated vertices - empty and nonempty dihypergraphs The design employed here is based off of #28613, but this PR does not depend on that one. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-combinatorics new-contributor	391/0	Mathlib.lean,Mathlib/Combinatorics/DiHypergraph/Basic.lean	2	2	['github-actions', 'mathlib4-merge-conflict-bot']	b-mehta assignee:b-mehta	86-32573 2 months ago	105-23600 3 months ago	168-11992 168 days
31147	daefigueroa author:daefigueroa	feat(Dynamics): point transitive monoid actions and transitive points	We define point transitivity for a monoid action on a topological space and define the set of transitive points. We add some basic lemmas and implications between topological transitivity and point transitivity. --- - [x] depends on: #28001 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-dynamics new-contributor	114/6	Mathlib/Dynamics/Transitive.lean	1	6	['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'sgouezel']	sgouezel assignee:sgouezel	86-30369 2 months ago	86-30369 2 months ago	18-38983 18 days
28613	espottesmith author:espottesmith	feat(Combinatorics): define undirected hypergraphs	This PR defines undirected hypergraphs: ``` @[ext] structure Hypergraph (α : Type*) where /-- The vertex set -/ vertexSet : Set α /-- The hyperedge set -/ hyperedgeSet : Set (Set α) /-- All hyperedges must be subsets of the vertex set -/ hyperedge_isSubset_vertexSet : ∀ ⦃e⦄, e ∈ hyperedgeSet → e ⊆ vertexSet ``` In addition to the main definition, some additional definitions and related lemmas are provided: - vertex adjacency - hyperedge adjacency - vertex "stars" - special cases (loops, empty hypergraphs, trivial hypergraphs, complete hypergraphs, simple hypergraphs, k-uniform hypergraphs, and d-regular hypergraphs) - (some) hypergraph cardinality - subhypergraphs, induced subhypergraphs, and partial hypergraphs This implementation is certainly bare-bones. I'm submitting this PR at this point, rather than when my developments are more fleshed out, because there has been some interest in others contributing to hypergraph formalization in mathlib. In the near future, goals include: - defining incidence matrices (i.e., conversion from `Hypergraph α` to `Matrix α (Set α) β` - coersion/generalization of graph as 2-uniform hypergraph - conversion of a hypergraph into its associated clique graph/two-section graph - constructing the dual of a hypergraph (note: on first blush, this appears somewhat challenging, given that we define hyperedges as `Set α` rather than some other type `β`) - rank and co-rank - walks, paths, cycles, etc. on hypergraphs --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-combinatorics new-contributor	375/0	Mathlib.lean,Mathlib/Combinatorics/Hypergraph/Basic.lean	2	54	['b-mehta', 'espottesmith', 'github-actions', 'jt496', 'lauramonk', 'mathlib4-merge-conflict-bot']	b-mehta assignee:b-mehta	84-49982 2 months ago	84-49984 2 months ago	101-37317 101 days
31987	saodimao20 author:saodimao20	feat: add monotonicity and relation lemmas for mgf and cgf	Add two lemmas about moment-generating and cumulant-generating functions: - `mgf_mono_in_t_of_nonneg`: For nonnegative random variables, the mgf is monotone in the parameter `t` - `cgf_zero_of_mgf_one`: The cgf equals zero iff the mgf equals one These lemmas are useful for studying properties of mgf and cgf in probability theory. Contributed by sequential-intelligence-lab(SIL), University of Virginia --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-measure-probability new-contributor	21/0	Mathlib/Probability/Moments/Basic.lean	1	5	['DavidLedvinka', 'github-actions']	RemyDegenne assignee:RemyDegenne	80-22475 2 months ago	80-22475 2 months ago	21-31799 21 days
32938	0xTerencePrime author:0xTerencePrime	feat(Order/LocallyFinite): prove DenselyOrdered and LocallyFiniteOrder are incompatible	## Summary This PR proves that a nontrivial densely ordered linear order cannot be locally finite. ## Main results * `not_locallyFiniteOrder`: A densely ordered locally finite linear order must be subsingleton. * `not_locallyFiniteOrder_of_nontrivial`: The main theorem - incompatibility of the two properties. Note: This implementation imports `Mathlib.Order.Interval.Set.Infinite` to reuse the existing `Set.Icc_infinite` theorem, ensuring standard library consistency. ## Mathematical content The key insight is that in a densely ordered type, we can always find a new element between any two distinct elements. This means any nontrivial interval contains infinitely many elements. However, `LocallyFiniteOrder` requires intervals to be finite. This contradiction implies that such a type cannot exist (unless it is trivial). ## Motivation This resolves a TODO mentioned in #7987 (Data/Finset/LocallyFinite entry). ## Verification - [x] `lake build Mathlib.Order.LocallyFinite.Basic` passes - [x] `lake exe runLinter Mathlib.Order.LocallyFinite.Basic` passes	awaiting-author t-order new-contributor	28/0	Mathlib/Order/Interval/Finset/Basic.lean	1	10	['0xTerencePrime', 'CoolRmal', 'github-actions', 'jcommelin', 'plp127']	nobody	75-45877 2 months ago	75-45917 2 months ago	3-22290 3 days
32698	farruhx author:farruhx	feat(List): add aesop / simp annotations to selected lemmas for improved automation	This PR adds `@[aesop safe]` and `@[simp]` annotations to a set of List lemmas whose proofs are routine and benefit from standardized automation. No statements or definitions are changed; only proof annotations are added. The lemmas updated in this PR are: * `or_exists_of_exists_mem_cons` * `append_subset_of_subset_of_subset` * `map_subset_iff` * `append_eq_has_append` * `append_right_injective` * `append_left_injective` * `reverse_surjective` * `reverse_bijective` * `mem_getLast?_append_of_mem_getLast?` * `mem_dropLast_of_mem_of_ne_getLast` * `idxOf_eq_length_iff` * `idxOf_append_of_mem` * `length_eraseP_add_one` The goal is to make these commonly used lemmas easier for `aesop`-based automation to resolve, while avoiding any interference with simp-normal-form lemmas or canonical rewrite rules. There are no API changes and no new theorems—only improved automation behavior.	awaiting-author new-contributor t-data	18/1	Mathlib/Data/List/Basic.lean	1	8	['artie2000', 'euprunin', 'farruhx', 'github-actions']	pechersky assignee:pechersky	74-80646 2 months ago	74-80646 2 months ago	7-31364 7 days
27817	zhuyizheng author:zhuyizheng	feat: add IMO2025P1	Add a solution to IMO2025P1, the original problem statement from https://github.com/jsm28/IMOLean --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict new-contributor IMO	1310/0	Archive.lean,Archive/Imo/Imo2025Q1.lean	2	9	['github-actions', 'kim-em', 'mathlib4-merge-conflict-bot', 'zhuyizheng']	dwrensha assignee:dwrensha	74-26443 2 months ago	74-26444 2 months ago	65-5080 65 days
26923	oliver-butterley author:oliver-butterley	feat(Dynamics/BirkhoffSum): add the pointwise ergodic theorem (Birkhoff's)	The Pointwise Ergodic Theorem, also known as Birkhoff's Ergodic Theorem. Co-authored-by: Lua Viana Reis - [x] depends on: #26074 - [x] depends on: #26807 - [x] depends on: #26810 - [x] depends on: #26840 - [x] depends on: #26842 - [x] depends on: #26848 - [x] depends on: #26851 - [x] depends on: #26852 - [x] depends on: #26853 - [x] depends on: #27008 - [x] depends on: #28901 Zulip: [PR thread](https://leanprover.zulipchat.com/#narrow/channel/144837-PR-reviews/topic/.2326923.20The.20pointwise.20ergodic.20theorem.20.28Birkhoff's.29/with/527835158) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-dynamics new-contributor	398/0	Mathlib.lean,Mathlib/Dynamics/BirkhoffSum/Pointwise.lean	2	31	['D-Thomine', 'github-actions', 'leanprover-community-bot-assistant', 'lua-vr', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'sgouezel', 'urkud']	sgouezel assignee:sgouezel	72-48866 2 months ago	78-6784 2 months ago	98-65140 98 days
33218	Blackfeather007 author:Blackfeather007	feat(Algebra): Define the associated graded ring to filtered ring	Define the associated graded ring to a filtered ring. --- - [ ] depends on: #33217 migrated from https://github.com/leanprover-community/mathlib4/pull/26858	blocked-by-other-PR new-contributor t-ring-theory	450/0	Mathlib.lean,Mathlib/RingTheory/FilteredAlgebra/AssociatedGraded.lean	2	n/a	['github-actions', 'mathlib4-dependent-issues-bot']	nobody	71-59108 2 months ago	unknown	unknown
33219	Blackfeather007 author:Blackfeather007	feat(Algebra): Define associated graded algebra	Define the associated graded algebra of a filtered algebra, constructed from a special case of associated graded ring. --- - [ ] depends on: #33218 migrated from #26859	blocked-by-other-PR new-contributor t-ring-theory	563/0	Mathlib.lean,Mathlib/RingTheory/FilteredAlgebra/AssociatedGraded.lean	2	n/a	['github-actions', 'mathlib4-dependent-issues-bot']	nobody	71-59000 2 months ago	unknown	unknown
33220	Blackfeather007 author:Blackfeather007	feat(Algebra): Define associated graded module	Define the associated graded module to a filtered module. --- - [ ] depends on: #33218 migrated from #26860	blocked-by-other-PR new-contributor t-ring-theory	669/0	Mathlib.lean,Mathlib/RingTheory/FilteredAlgebra/AssociatedGraded.lean	2	n/a	['github-actions', 'mathlib4-dependent-issues-bot']	nobody	71-58916 2 months ago	unknown	unknown
33227	Blackfeather007 author:Blackfeather007	feat(Algebra): exact of associated graded exact	We proved that a chain complex is exact if its associated graded complex is exact. Co-authored-by: Huanyu Zheng @Yu-Misaka [suzuka@misaka-yu.com](mailto:suzuka@misaka-yu.com) Co-authored-by: Yi Yuan @yuanyi-350 [kysyy1@126.com](mailto:kysyy1@126.com) Co-authored-by: Weichen Jiao @AlbertJ-314 [albertjiao314@gmail.com](mailto:albertjiao314@gmail.com) --- - [ ] depends on: #33226 migrated from #26869	blocked-by-other-PR new-contributor t-ring-theory	728/0	Mathlib.lean,Mathlib/RingTheory/FilteredAlgebra/AssociatedGraded.lean,Mathlib/RingTheory/FilteredAlgebra/Exactness.lean,Mathlib/RingTheory/FilteredAlgebra/FilteredHom.lean	4	n/a	['github-actions', 'mathlib4-dependent-issues-bot']	nobody	71-56588 2 months ago	unknown	unknown
33226	Blackfeather007 author:Blackfeather007	feat(Algebra): associated graded exact of exact and strict	In this file, we define the concept of exhaustive filtrations. We also prove a AssociatedGradedRingHom sequence is exact iff each GradedPieceHom is exact. And when a sequence is strict exact, the corresponding AssociatedGradedRingHom sequence is also exact. Co-authored-by: Huanyu Zheng @Yu-Misaka [suzuka@misaka-yu.com](mailto:suzuka@misaka-yu.com) Co-authored-by: Yi Yuan @yuanyi-350 [kysyy1@126.com](mailto:kysyy1@126.com) Co-authored-by: Weichen Jiao @AlbertJ-314 [albertjiao314@gmail.com](mailto:albertjiao314@gmail.com) --- - [ ] depends on: #33222 migrated from #26868	blocked-by-other-PR new-contributor t-ring-theory	529/0	Mathlib.lean,Mathlib/RingTheory/FilteredAlgebra/AssociatedGraded.lean,Mathlib/RingTheory/FilteredAlgebra/Exactness.lean,Mathlib/RingTheory/FilteredAlgebra/FilteredHom.lean	4	2	['github-actions', 'mathlib4-dependent-issues-bot']	nobody	71-56586 2 months ago	71-56587 2 months ago	0-3424 57 minutes
33225	Blackfeather007 author:Blackfeather007	feat(Algebra): filtered module hom	In this PR we defined the filtered semi-linear map for filtered module and the associated graded module hom. --- - [ ] depends on: #33220 - [ ] depends on: #33223 migrated from #26867	blocked-by-other-PR new-contributor t-ring-theory	1205/0	Mathlib.lean,Mathlib/RingTheory/FilteredAlgebra/AssociatedGraded.lean,Mathlib/RingTheory/FilteredAlgebra/FilteredHom.lean	3	n/a	['github-actions', 'mathlib4-dependent-issues-bot']	nobody	71-56585 2 months ago	unknown	unknown
33224	Blackfeather007 author:Blackfeather007	feat(Algebra): define filtered alghom	In this PR, we define the filtered algebra homomorphisms on algebras and prove some basic properties of them. --- - [ ] depends on: #33219 - [ ] depends on: #33223 migrated from #26863	blocked-by-other-PR new-contributor t-ring-theory	1055/0	Mathlib.lean,Mathlib/RingTheory/FilteredAlgebra/AssociatedGraded.lean,Mathlib/RingTheory/FilteredAlgebra/FilteredHom.lean	3	n/a	['github-actions', 'mathlib4-dependent-issues-bot']	nobody	71-56583 2 months ago	unknown	unknown
33222	Blackfeather007 author:Blackfeather007	feat(Algebra): define filtered add group hom	In this file we define filtered hom and the corresponding associated graded hom for abelian groups. Co-authored-by: Huanyu Zheng @Yu-Misaka [suzuka@misaka-yu.com](mailto:suzuka@misaka-yu.com) Co-authored-by: Yi Yuan @yuanyi-350 [kysyy1@126.com](mailto:kysyy1@126.com) Co-authored-by: Weichen Jiao @AlbertJ-314 [albertjiao314@gmail.com](mailto:albertjiao314@gmail.com) --- - [ ] depends on: #33217 migrated from #26861	blocked-by-other-PR new-contributor t-ring-theory	368/0	Mathlib.lean,Mathlib/RingTheory/FilteredAlgebra/AssociatedGraded.lean,Mathlib/RingTheory/FilteredAlgebra/FilteredHom.lean	3	2	['github-actions', 'mathlib4-dependent-issues-bot']	nobody	71-56579 2 months ago	71-56580 2 months ago	0-3900 1 hour
33178	gw90 author:gw90	feat(Analysis/CStarAlgebra/Spectrum): Adding lemmas that the CStarAlgebra norm equals the square root of the spectral radius of star a * a	Adds lemmas that the \|\|a\|\|^2_A=sqrt(spectralRadius C (star a * a)). I think it would be helpful to have these lemmas available in Mathlib. It'll help with some of the other things I'm working on. Feel free to move them to a different file or rename them as you see fit.	awaiting-author t-analysis new-contributor	24/0	Mathlib/Analysis/CStarAlgebra/Spectrum.lean	1	15	['github-actions', 'gw90', 'themathqueen', 'vihdzp']	nobody	71-8447 2 months ago	72-70466 2 months ago	0-15209 4 hours
32960	dleijnse author:dleijnse	feat(FieldTheory): adjoin pth roots	For a field `k` of exponential characteristic `p` and a subset `S` of `k`, we define the extension of `k` obtained by adjoining all `p`-th roots of elements of `S`. We prove that this is a purely inseparable extension, and provide some basic API. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-algebra new-contributor label:t-algebra$	131/0	Mathlib.lean,Mathlib/FieldTheory/PurelyInseparable/AdjoinPthRoots.lean	2	13	['artie2000', 'chrisflav', 'dleijnse', 'erdOne', 'github-actions', 'leanprover-radar']	erdOne assignee:erdOne	67-15317 2 months ago	67-15317 2 months ago	10-12739 10 days
33163	Aaron1011 author:Aaron1011	feat: prove subgroup of (M -> Z) is finitely generated	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author new-contributor t-ring-theory	5/0	Mathlib/RingTheory/DedekindDomain/Dvr.lean	1	2	['erdOne', 'github-actions']	alreadydone assignee:alreadydone	67-8267 2 months ago	67-8267 2 months ago	5-82474 5 days
33133	0xTerencePrime author:0xTerencePrime	feat(Algebra/Group/Center): add Decidable (IsMulCentral a) instance	This PR adds a `Decidable` instance for `IsMulCentral a`. ### Summary The structure `IsMulCentral` was missing a `Decidable` instance. This PR provides the instance by leveraging `isMulCentral_iff`, enabling decidability for both multiplicative and additive (via `to_additive`) structures. ### Verification - `lake build Mathlib.Algebra.Group.Center` passed. - `lake exe runLinter Mathlib.Algebra.Group.Center` passed.	awaiting-author t-algebra new-contributor label:t-algebra$	7/0	Mathlib/Algebra/Group/Center.lean	1	3	['github-actions', 'robin-carlier']	ocfnash assignee:ocfnash	61-36458 2 months ago	61-36458 2 months ago	12-60805 12 days
33502	MrQubo author:MrQubo	fix(Tactic/ProxyType): Pass params explicitly in proxy_equiv% implementation	Fix [#mathlib4 > `deriving Fintype` with Prop](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/.60deriving.20Fintype.60.20with.20Prop/with/566118621) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP t-meta new-contributor	12/2	Mathlib/Tactic/ProxyType.lean,MathlibTest/DeriveFintype.lean	2	7	['MrQubo', 'github-actions', 'kmill']	kmill assignee:kmill	60-3382 2 months ago	60-3383 2 months ago	0-60133 16 hours
22657	Xmask19 author:Xmask19	feat: a graph is maximally acyclic iff it is a tree	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-combinatorics new-contributor	86/0	Mathlib/Combinatorics/SimpleGraph/Acyclic.lean	1	8	['Rida-Hamadani', 'SnirBroshi', 'b-mehta', 'github-actions', 'grunweg', 'mathlib4-merge-conflict-bot']	b-mehta assignee:b-mehta	59-82875 2 months ago	143-83304 4 months ago	0-0 0 seconds
17176	arulandu author:arulandu	feat: integrals and integrability with .re	Lemmas for swapping order of .re and integration/integrability. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author please-adopt merge-conflict t-measure-probability new-contributor	49/0	Mathlib/MeasureTheory/Function/L1Space.lean,Mathlib/MeasureTheory/Integral/IntegrableOn.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral.lean,Mathlib/MeasureTheory/Integral/SetIntegral.lean	4	32	['EtienneC30', 'arulandu', 'github-actions', 'loefflerd']	nobody	58-6380 1 month ago	58-6380 1 month ago	0-0 0 seconds
33330	michael-novak-math author:michael-novak-math	feat: add arc-length reparametrization of parametrized curves	add new definitions of arc-length reparametrization and its corresponding parameter transformation and a theorem establishing the desired properties.	merge-conflict t-analysis new-contributor	311/0	Mathlib.lean,Mathlib/Analysis/Calculus/ArcLengthReparametrization.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/FundThmCalculus.lean,docs/references.bib,lake-manifest.json	5	53	['SnirBroshi', 'github-actions', 'grunweg', 'j-loreaux', 'mathlib4-merge-conflict-bot', 'michael-novak-math']	j-loreaux assignee:j-loreaux	55-73735 1 month ago	55-73736 1 month ago	6-81888 6 days
33299	kingiler author:kingiler	feat: Add decidable membership for Interval	Implemented membership and corresponding decidable instance for `Interval`. Related [#mathlib4 > Proposal: Add decidable membership for Interval](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Proposal.3A.20Add.20decidable.20membership.20for.20Interval/with/565438009). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-order new-contributor	16/1	Mathlib/Order/Interval/Basic.lean	1	5	['Vierkantor', 'eric-wieser', 'github-actions', 'kingiler']	Vierkantor assignee:Vierkantor	55-16686 1 month ago	55-16686 1 month ago	13-42146 13 days
30142	shalliso author:shalliso	feat(Topology/Baire): define IsNonMeagre	non-meagre sets (also known as "of the second category") are worthy of their own definition and API. This was useful to me for formalizing a result of "automatic continuity", that is, a Baire-measurable homomorphism between Polish groups must be continuous. Simply working with the negation of IsMeagre quickly became cumbersome, and non-meagre sets have an important role in the study of Polish (e.g. locally compact) groups. From https://github.com/shalliso/automatic_continuity [ ] depends on: #30141 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-topology new-contributor	83/1	Mathlib/Topology/Baire/NonMeagre.lean,Mathlib/Topology/GDelta/Basic.lean	2	2	['github-actions', 'mathlib4-merge-conflict-bot']	nobody	54-26370 1 month ago	54-26371 1 month ago	98-58846 98 days
32880	0xTerencePrime author:0xTerencePrime	feat(Analysis/Asymptotics): define subpolynomial growth	## Main definitions * `Asymptotics.IsSubpolynomial l f g`: A function `f` has subpolynomial growth with respect to `g` along filter `l` if `f = O(1 + ‖g‖^k)` for some natural `k`. ## Main results * `IsSubpolynomial.const`: Constant functions have subpolynomial growth * `IsSubpolynomial.id`: Identity has subpolynomial growth * `IsSubpolynomial.add`: Closure under addition * `IsSubpolynomial.neg`: Closure under negation * `IsSubpolynomial.sub`: Closure under subtraction * `IsSubpolynomial.mul`: Closure under multiplication * `IsSubpolynomial.pow`: Closure under powers * `isSubpolynomial_iff_one_add`: Equivalence with `(1 + ‖g‖)^k` formulation * `IsSubpolynomial.uniform`: Uniform bounds for finite families ## Implementation notes The definition uses `1 + ‖g‖^k` rather than `(1 + ‖g‖)^k` as the primary form, with the equivalence established in `isSubpolynomial_iff_one_add`. Four private auxiliary lemmas handle the key inequalities needed for closure proofs. Closes #32658	awaiting-author t-analysis new-contributor	185/0	Mathlib.lean,Mathlib/Analysis/Asymptotics/Subpolynomial.lean	2	28	['0xTerencePrime', 'ADedecker', 'github-actions', 'j-loreaux']	ADedecker assignee:ADedecker	51-9454 1 month ago	51-9675 1 month ago	23-56215 23 days
33948	anivegesana author:anivegesana	feat(Analysis/Normed/Algebra): matrix exponential of nilpotent matrix	Where the matrix exponential and nilpotent elements are defined, both the matrix exponential and the nilpotent element exponential. I had to add a different theorem for normed space exponential and the matrix exponential since the right instances wouldn't be synthesized. Help with golfing would be appreciated. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-analysis new-contributor	34/0	Mathlib/Analysis/Normed/Algebra/Exponential.lean,Mathlib/Analysis/Normed/Algebra/MatrixExponential.lean	2	1	['github-actions']	nobody	49-60439 1 month ago	49-60445 1 month ago	49-60484 49 days
31610	rudynicolop author:rudynicolop	feat(Computability/NFA): Kleene star closure for Regular Languages via NFA	This PR constructs a Kleene star closure for non-epsilon NFAs, and proves that regular languages are closed under Kleene star. The NFA construction is `NFA.kstar`. The main theorems are: - `NFA.accepts_kstar`: demonstrates that `M.kstar` accepts the Kleene star closure of the language of `M`. - `IsRegular.kstar`: demonstrates that regular languages are closed under Kleene star. There is an onging zulip discussion about regular languages in Mathlib: https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Regular.20languages.3A.20the.20review.20queue/with/553759136 This discussion is also tracked at #24205. Furthermore, the construction and proofs in this PR are heavily inspired by @TpmKranz from his #15651. #15651 supersedes this PR, so if it is accepted then this PR is not needed. --- - [x] depends on: #31038 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author awaiting-CI new-contributor t-computability	405/7	Mathlib/Computability/NFA.lean	1	16	['YaelDillies', 'ctchou', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	YaelDillies assignee:YaelDillies	49-11192 1 month ago	49-11192 1 month ago	43-77956 43 days
30391	rudynicolop author:rudynicolop	feat(Data/List): list splitting definitions and lemmas	This PR continues the work from #24395. Original PR: https://github.com/leanprover-community/mathlib4/pull/24395	awaiting-author new-contributor t-data	108/2	Mathlib/Data/List/Perm/Lattice.lean,Mathlib/Data/List/TakeDrop.lean	2	50	['BoltonBailey', 'IlPreteRosso', 'TwoFX', 'Vierkantor', 'github-actions', 'kckennylau', 'mathlib4-merge-conflict-bot', 'rudynicolop']	TwoFX assignee:TwoFX	47-27785 1 month ago	47-36307 1 month ago	93-10641 93 days
34005	MSpill author:MSpill	feat: inverse function theorem for manifolds (concrete version)	Proves the inverse function theorem for manifolds: given manifolds $M, N$ and a $C^n$ map $f : M \to N$ whose differential is a linear isomorphism at $p \in M$, then $f$ is a local diffeomorphism at $p$, provided that both $p$ and its image are interior points. The proof proceeds in 4 main steps: 1. Define composition of partial diffeomorphisms 2. Show that the extended chart at an interior point can be restricted to an open set on which it is a partial diffeomorphism, viewing the model vector space as a manifold modelled on itself trivially 3. Use the inverse function theorem (applied to $f$ written in coordinates) to obtain a partial diffeomorphism between model vector spaces 4. Compose with chart diffeomorphisms to obtain a partial diffeomorphism between the manifolds. ------ [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-differential-geometry new-contributor	232/3	Mathlib/Geometry/Manifold/LocalDiffeomorph.lean	1	n/a	['MSpill', 'github-actions', 'grunweg']	grunweg assignee:grunweg	46-17736 1 month ago	unknown	unknown
29282	Jlh18 author:Jlh18	feat(CategoryTheory): HasColimits instance on Grpd	Show that the category of groupoids has all small colimits, as a coreflective subcategory of `Cat`, which has all small colimits. The right adjoint of the forgetful functor is the core functor `CategoryTheory.Core.functor`. - [ ] depends on: #29283 [Core of a category as a functor] --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-category-theory new-contributor	140/4	Mathlib.lean,Mathlib/AlgebraicTopology/FundamentalGroupoid/InducedMaps.lean,Mathlib/CategoryTheory/Category/Grpd.lean,Mathlib/CategoryTheory/Core.lean,Mathlib/CategoryTheory/Groupoid/Grpd/Colimit.lean,Mathlib/CategoryTheory/Groupoid/Grpd/Core.lean	6	3	['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	45-37865 1 month ago	45-37865 1 month ago	0-396 6 minutes
32039	HugLycan author:HugLycan	feat(Tactic/Positivity): handle non-zeroness in non-orders	--- WIP... [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP merge-conflict t-meta new-contributor	618/163	Mathlib/Algebra/Order/AbsoluteValue/Basic.lean,Mathlib/Algebra/Order/BigOperators/Expect.lean,Mathlib/Algebra/Order/BigOperators/Ring/Finset.lean,Mathlib/Algebra/Order/Field/Basic.lean,Mathlib/Algebra/Order/Field/Power.lean,Mathlib/Algebra/Order/Module/Algebra.lean,Mathlib/Tactic/Positivity/Basic.lean,Mathlib/Tactic/Positivity/Core.lean,Mathlib/Tactic/Positivity/Finset.lean,Mathlib/Tactic/Positivity/test_Basic.lean	10	3	['github-actions', 'mathlib4-merge-conflict-bot']	nobody	44-44319 1 month ago	51-26154 1 month ago	0-16 16 seconds
32745	LTolDe author:LTolDe	feat(Topology/Algebra): add MulActionConst.lean	add Topology/Algebra/MulActionConst.lean introduce class `ContinuousSMulConst` for a scalar multiplication that is continuous in the first argument, in analogy to `ContinuousConstSMul` define `MulAction.ball x U` as the set `U • {x}` given `[SMul G X] (x : X) (U : Set G)` The lemmas shown here will be useful to prove the Effros Theorem, see [zulip](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Effros.20Theorem/with/558712441). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-topology new-contributor	117/0	Mathlib.lean,Mathlib/Topology/Algebra/MulActionConst.lean	2	8	['LTolDe', 'github-actions', 'urkud']	dagurtomas assignee:dagurtomas	44-23731 1 month ago	51-3261 1 month ago	32-14897 32 days
33478	anishrajeev author:anishrajeev	feat(ModelTheory): define a subset of the topology over complete types	Define a subset of the Stone Space over a language expanded with countably many constants. Define the proposition to indicate if a language is countable. The subset's density and openness is a future goal to prove (have a branch where it is almost finished), in pursuit of formalizing the proof of the Omitting Types Theorem via properties of Baire spaces. - [ ] depends on: #32215 - [ ] depends on: #32546	blocked-by-other-PR merge-conflict t-logic new-contributor	160/1	Mathlib.lean,Mathlib/ModelTheory/Topology/Types.lean,Mathlib/ModelTheory/Types.lean,Mathlib/Tactic/Linter/DirectoryDependency.lean	4	8	['NoneMore', 'anishrajeev', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'tb65536']	nobody	43-17250 1 month ago	48-945 1 month ago	10-38484 10 days
32546	anishrajeev author:anishrajeev	feat(ModelTheory): Prove compactness of the type space	Define the space of types and prove various topological properties of it (zero dimensional, totally separated, compact, baire). The goal is to formalize the proof of the Omitting Types Theorem - [ ] depends on: #32215	merge-conflict t-logic new-contributor	127/1	Mathlib.lean,Mathlib/ModelTheory/Topology/Types.lean,Mathlib/ModelTheory/Types.lean,Mathlib/Tactic/Linter/DirectoryDependency.lean	4	6	['NoneMore', 'anishrajeev', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	fpvandoorn assignee:fpvandoorn	43-17200 1 month ago	43-17203 1 month ago	3-84208 3 days
31092	FlAmmmmING author:FlAmmmmING	feat(Algebra/Group/ForwardDiff.lean): Add theorem `sum_shift_eq_fwdDiff_iter`.	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated t-algebra new-contributor label:t-algebra$	17/1	Mathlib/Algebra/Group/ForwardDiff.lean	1	20	['BeibeiX0', 'FlAmmmmING', 'Ruben-VandeVelde', 'dagurtomas', 'github-actions', 'jcommelin', 'mathlib-bors', 'mathlib4-merge-conflict-bot']	dagurtomas assignee:dagurtomas	41-24750 1 month ago	41-24750 1 month ago	54-22055 54 days
34141	gululu996-ui author:gululu996-ui	feat(Combinatorics/SimpleGraph/Acyclic): finite trees have at least two degree-one vertices	Add a lemma showing that a finite tree with at least two vertices has at least two vertices of degree 1. - Introduce a helper lemma `SimpleGraph.Connected.one_le_degree` for connected graphs on a nontrivial finite type. - Prove the leaf-count lower bound via the degree-sum identity and a counting argument. ---	awaiting-author t-combinatorics new-contributor	72/2	Mathlib/Combinatorics/SimpleGraph/Acyclic.lean	1	9	['IvanRenison', 'SnirBroshi', 'github-actions', 'vlad902']	nobody	41-21008 1 month ago	41-26367 1 month ago	1-23617 1 day
34129	idontgetoutmuch author:idontgetoutmuch	feat: define Ehresmann connections	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-differential-geometry new-contributor	90/0	Mathlib.lean,Mathlib/Geometry/Manifold/EhresmannConnection.lean	2	5	['github-actions', 'grunweg', 'idontgetoutmuch', 'metakunt']	nobody	40-42558 1 month ago	42-30212 1 month ago	2-10278 2 days
31377	CoolRmal author:CoolRmal	feat: a series of smooth functions that converges (locally) uniformly is smooth	The main theorem is the proof that an infinite sum of $C^n$ functions on a one-dimensional domain which converges locally uniformly is $C^n$ and related results. This should be compared with [contDiff_tsum](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Analysis/Calculus/SmoothSeries.html#contDiff_tsum) where the same result is proved for functions on an arbitrary domain but with a slightly stronger convergence assumption. The main motivation for this PR is the [#mathlib4 > Tychonov's Counterexample for the Heat Equation](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Tychonov's.20Counterexample.20for.20the.20Heat.20Equation/with/547367912). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-topology new-contributor	110/18	Mathlib/Analysis/Calculus/SmoothSeries.lean,Mathlib/Analysis/SpecialFunctions/Trigonometric/Cotangent.lean,Mathlib/NumberTheory/ModularForms/EisensteinSeries/QExpansion.lean,Mathlib/Topology/Algebra/InfiniteSum/TsumUniformlyOn.lean,Mathlib/Topology/Algebra/InfiniteSum/UniformOn.lean	5	20	['CoolRmal', 'github-actions', 'mathlib4-merge-conflict-bot', 'ocfnash', 'sgouezel']	ocfnash assignee:ocfnash	35-3106 1 month ago	35-3107 1 month ago	8-15568 8 days
33031	chiyunhsu author:chiyunhsu	feat(Combinatorics/Enumerative/Partition): add combinatorial proof of Euler's partition theorem	The new file EulerComb.lean contains the combinatorial proof of Euler's partition theorem. The analytic proof of the theorem and its generalization of Glaisher's Theorem has already been formalized in [Glaisher.lean](https://github.com/leanprover-community/mathlib4/blob/master/Mathlib/Combinatorics/Enumerative/Partition/Glaisher.lean). The generalization of the combinatorial proof from this file to Glaisher's Theorem is within reach. --- Zulip discussion: [#mathlib4 > Glaisher’s Bijection on integer partitions](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Glaisher.E2.80.99s.20Bijection.20on.20integer.20partitions/with/570808111) [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-combinatorics new-contributor awaiting-zulip	531/0	Mathlib.lean,Mathlib/Combinatorics/Enumerative/Partition/EulerComb.lean	2	5	['chiyunhsu', 'github-actions', 'tb65536', 'vihdzp']	b-mehta assignee:b-mehta	34-26627 1 month ago	34-26627 1 month ago	42-25715 42 days
33817	FlAmmmmING author:FlAmmmmING	fix(Combinatorics/Enumerative/Schroder.lean): Fix the definition and theorem of smallSchroder.	In the previous definition, the small Schröder numbers were defined as ```LaTeX s_0 = 1, s_1 = 1, s_2 = 1, s_3 = 3... ``` , which does not match the sequence listed in OEIS A006318. Moreover, this definition makes it difficult to correctly write the generating function for the small Schröder numbers. This PR fixes this issue. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-combinatorics new-contributor large-import	61/39	Mathlib/Combinatorics/Enumerative/Schroder.lean	1	19	['FlAmmmmING', 'github-actions', 'vihdzp']	awainverse assignee:awainverse	33-74721 1 month ago	53-35433 1 month ago	53-35478 53 days
34227	stepan2698-cpu author:stepan2698-cpu	feat: If sum of densities is at least one, the sumset covers the naturals	Proves an outstanding TODO item from Mathlib.Combinatorics.Schnirelmann : shows that if the sum of two densities is at least one, the sumset covers the positive naturals. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-combinatorics new-contributor	51/1	Mathlib/Combinatorics/Schnirelmann.lean	1	3	['github-actions', 'grunweg', 'kbuzzard']	awainverse assignee:awainverse	33-74718 1 month ago	42-8732 1 month ago	42-8776 42 days
34130	FlAmmmmING author:FlAmmmmING	feat(Combinatorics/SimpleGraph/Acyclic): Add new theorem `isTree_iff_uniqueShortest_path`	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-combinatorics new-contributor	28/1	Mathlib/Combinatorics/SimpleGraph/Acyclic.lean	1	9	['IvanRenison', 'github-actions', 'metakunt', 'vlad902']	nobody	33-49034 1 month ago	42-33049 1 month ago	2-6832 2 days
34028	floor-licker author:floor-licker	feat(SimpleGraph): add max-flow/min-cut weak duality	This PR introduces a basic s–t flow setup for undirected SimpleGraphs and proves the standard weak-duality inequality: for any feasible flow f and any s–t cut S, value f ≤ cutCapacity S. This is a small, self-contained lemma I extracted while working on larger graph-theoretic formalizations, in particular, results that will ultimately rely on a full max-flow/min-cut theorem. The full MFMC equality/existence statement is not included here. This is the weak-duality direction (∀ f S, value f ≤ cutCapacity S).	t-combinatorics new-contributor	169/0	Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/MaxFlowMinCut.lean	2	13	['SnirBroshi', 'floor-licker', 'github-actions']	kmill assignee:kmill	32-74728 1 month ago	47-67820 1 month ago	47-67859 47 days
32609	PrParadoxy author:PrParadoxy	feat(LinearAlgebra/PiTensorProduct): Relation between nested tensor products and tensor products indexed by dependent sums	Product tensors in `⨂ j : (Σ i, β i), s j.fst j.snd` can be mapped to product tensors in `⨂ i, ⨂ b : β i, s i b`. If the outer index type is finite, the two types are equivalent. This allows the definition of endomorphisms on PiTensorProducts by specifying them on disjoint subsets of the index set. Such constructions are common e.g. in quantum circuits, quantum cellular automata, and renormalization procedures. --- WIP. This PR contains two "requests for comments". Essentially: * Is a single complex-to-define linear equivalence preferable over several less complex ones, which might however be of limited interest by themselves? * Which trade-offs are appropriate to make things computable? - [ ] depends on: #32608 - [x] depends on: #32600 - [x] depends on: #32598 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-algebra new-contributor label:t-algebra$	683/0	Mathlib.lean,Mathlib/Data/Sigma/Basic.lean,Mathlib/LinearAlgebra/Multilinear/Basic.lean,Mathlib/LinearAlgebra/PiTensorProduct/Nested.lean,Mathlib/LinearAlgebra/PiTensorProduct/Set.lean	5	5	['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	32-439 1 month ago	32-439 1 month ago	0-2004 33 minutes
33520	NoneMore author:NoneMore	feat(ModelTheory/ElementarySubstructures): add a variant of Tarski-Vaught test taking sets as input	There should exist an `ElementarySubstructure.copy` such that we can directly bundle the set itself instaed of its closure as an elementary substructure. The other direction depends on #33458. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-logic new-contributor	55/0	Mathlib/ModelTheory/ElementarySubstructures.lean	1	3	['Citronhat', 'NoneMore', 'github-actions']	awainverse assignee:awainverse	31-74679 1 month ago	60-37840 2 months ago	60-37873 60 days
30260	imbrem author:imbrem	feat(CategoryTheory/Monoidal): added CocartesianMonoidalCategory	As discussed in #21603 and #28718; this implements chosen finite coproducts on top of `AddMonoidalCategory` as defined in #30150 --- - [ ] depends on: #30150 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-category-theory new-contributor large-import	839/125	Mathlib.lean,Mathlib/CategoryTheory/Monoidal/Category.lean,Mathlib/CategoryTheory/Monoidal/Cocartesian/Basic.lean,Mathlib/CategoryTheory/Monoidal/Discrete.lean,Mathlib/Tactic/ToAdditive/GuessName.lean	5	4	['github-actions', 'imbrem', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	31-39270 1 month ago	31-39270 1 month ago	0-1234 20 minutes
30258	imbrem author:imbrem	feat(CategoryTheory/Monoidal): to_additive for proofs using `monoidal`	Building on #30150, this allows us to use `@[to_additive]` on proofs containing `monoidal`, by tagging the lemmas `monoidal` outputs with `@[to_additive]` as appropriate. Testing on my branch [`additive-monoidal-coherence`](https://github.com/imbrem/mathlib4/tree/additive-monoidal-coherence) shows that this works. It is still future work to have either the `monoidal` tactic or a new `add_monoidal` tactic work for `AddMonoidalCategory` instances directly. --- - [ ] depends on: #30150 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-category-theory new-contributor large-import	524/140	Mathlib/CategoryTheory/Monoidal/Category.lean,Mathlib/CategoryTheory/Monoidal/Discrete.lean,Mathlib/Tactic/CategoryTheory/Monoidal/Normalize.lean,Mathlib/Tactic/CategoryTheory/Monoidal/PureCoherence.lean,Mathlib/Tactic/CategoryTheory/MonoidalComp.lean,Mathlib/Tactic/ToAdditive/GuessName.lean	6	3	['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	31-39263 1 month ago	31-39263 1 month ago	0-241 4 minutes
32608	PrParadoxy author:PrParadoxy	feat(LinearAlgebra/PiTensorProduct): API for PiTensorProducts indexed by sets	This PR addresses a TODO item in LinearAlgebra/PiTensorProduct.lean: * API for the various ways ι can be split into subsets; connect this with the binary tensor product -- specifically by describing tensors of type ⨂ (i : S), M i, for S : Set ι. Our primary motivation is to formalise the notion of "restricted tensor products". This will be the content of a follow-up PR. Beyond that, the Set API is natural in contexts where the index type has an independent interpretation. An example is quantum physics, where ι ranges over distinguishable degrees of freedom, and where its is common practice to annotate objects by the set of indices they are defined on. --- Stub file with preliminary definition of the restricted tensor product as a direct limit of tensors indexed by finite subsets of an index type: https://github.com/PrParadoxy/mathlib4/blob/restricted-stub/Mathlib/LinearAlgebra/PiTensorProduct/Restricted.lean --- - [x] depends on: #32598 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-algebra new-contributor awaiting-zulip label:t-algebra$	300/2	Mathlib.lean,Mathlib/LinearAlgebra/PiTensorProduct.lean,Mathlib/LinearAlgebra/PiTensorProduct/Set.lean	3	28	['PrParadoxy', 'dagurtomas', 'eric-wieser', 'github-actions', 'goliath-klein', 'leanprover-radar', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	dagurtomas assignee:dagurtomas	31-39232 1 month ago	31-39232 1 month ago	10-66980 10 days
32742	LTolDe author:LTolDe	feat(MeasureTheory/Constructions/Polish/Basic): add class SuslinSpace	add new class `SuslinSpace` for a topological space that is an analytic set in itself This will be useful to prove the Effros Theorem, see [zulip thread](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Effros.20Theorem/with/558712441). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-measure-probability new-contributor awaiting-zulip	4/0	Mathlib/MeasureTheory/Constructions/Polish/Basic.lean	1	9	['ADedecker', 'LTolDe', 'dupuisf', 'github-actions', 'jcommelin']	PatrickMassot assignee:PatrickMassot	31-39037 1 month ago	31-39037 1 month ago	25-83455 25 days
33109	felixpernegger author:felixpernegger	feat(Data/Nat/Choose): Binomial inversion	This PR adds binomial inversion (also called binomial transform), which is a useful method for proving binomial identities. It is tricky to find direct references to binomial inversion, but for example [this](https://en.wikipedia.org/wiki/Binomial_transform#Binomial_convolution) Wikipedia article mentions it ("The formula"). The first theorem ```alternating_sum_choose_mul_of_alternating_sum_choose_mul``` could be refined (we only need the hypothesis ```h``` up to some point), but this seems to needlessly complicate it.	awaiting-author new-contributor t-data	107/0	Mathlib.lean,Mathlib/Data/Nat/Choose/Inversion.lean	2	6	['dagurtomas', 'felixpernegger', 'github-actions', 'thomaskwaring', 'wwylele']	dagurtomas assignee:dagurtomas	31-38906 1 month ago	31-38906 1 month ago	33-67952 33 days
30121	idontgetoutmuch author:idontgetoutmuch	feat(Mathlib/Geometry/Manifold): principal fiber bundle core	A structure capturing what it means to be a principal fibre bundle. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-differential-geometry new-contributor	227/0	Mathlib.lean,Mathlib/Geometry/Manifold/PrincipalFiberBundle/PrincipalGBundle.lean	2	8	['github-actions', 'grunweg', 'idontgetoutmuch', 'mathlib4-merge-conflict-bot']	hrmacbeth assignee:hrmacbeth	31-30978 1 month ago	43-30048 1 month ago	25-22983 25 days
31102	JOSHCLUNE author:JOSHCLUNE	feat: require LeanHammer	Experimenting with adding LeanHammer as a mathlib dependency --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-meta new-contributor	61/4	Mathlib/Tactic/Common.lean,Mathlib/Tactic/Linter/DirectoryDependency.lean,MathlibTest/Hammer.lean,lake-manifest.json,lakefile.lean	5	2	['github-actions', 'mathlib4-merge-conflict-bot']	nobody	31-29745 1 month ago	31-29746 1 month ago	19-46677 19 days
33431	gululu996-ui author:gululu996-ui	feat(Combinatorics/SimpleGraph/Bipartite): characterize bipartite simple graphs by even cycles	Add the classical characterization of bipartite simple graphs: a simple graph is bipartite if and only if every cycle has even length. Previously, mathlib has the definition of `IsBipartite` for `SimpleGraph` and various lemmas about bipartite graphs, but it does not provide this equivalence in a single theorem, so users have to reprove or reassemble it from existing results. Prove the forward direction by showing a 2-coloring alternates along any walk, so every cycle must have even length. Prove the converse by showing that if an odd cycle exists then no bipartition is possible, hence if all cycles are even the graph admits a bipartition.	awaiting-author t-combinatorics new-contributor	186/1	Mathlib/Combinatorics/SimpleGraph/Bipartite.lean	1	5	['NickAdfor', 'github-actions', 'jcommelin']	kmill assignee:kmill	31-29477 1 month ago	33-30374 1 month ago	30-2643 30 days
34007	martinwintermath author:martinwintermath	feat(Algebra/Module/Submodule/Dual): dual operator for submodules	Add new file `Dual.lean` that defines the dual operator for submodules. The main definition is * `Submodule.dual`: given a bilinear pairing `p` between two `R`-modules `M` and `N` and a set `s` in `M`, `Submodule.dual p s` is the submodule in `N` consisting of all points `y` such that `0 = p x y` for all `x ∈ s`. This implementation of the `dual` operator for submodules is written to parallel the implementation of `PointedCone.dual`. Include some additional results: * theorems that represent the dual as the kernel of a linear map * theorems for the relation between dual and the `dualAnnihilator` and `dualCoannihilator` of a submodule. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-algebra new-contributor label:t-algebra$	236/0	Mathlib.lean,Mathlib/Algebra/Module/Submodule/Dual.lean	2	5	['github-actions', 'joelriou', 'martinwintermath']	joelriou assignee:joelriou	31-25514 1 month ago	33-7973 1 month ago	14-81380 14 days
34375	jvanwinden author:jvanwinden	feat(MeasureTheory/Function/AEEqOfLIntegral): introduce lemmas for rewriting a.e. inequalities	Introduce the following lemmas: - ae_le_const_iff_forall_gt_imp_ae_lt, - ae_const_le_iff_forall_lt_imp_ae_gt, - ae_le_const_iff_forall_gt_imp_ae_le, - ae_const_le_iff_forall_lt_imp_ae_ge, which can be used get an epsilon of room in a.e. inequalities, with the epsilon being outside the a.e. quantifier. The 'le/ge' variants require a dense ordering. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-measure-probability new-contributor	24/0	Mathlib/MeasureTheory/Function/AEEqOfLIntegral.lean	1	4	['github-actions', 'jvanwinden', 'urkud']	kex-y assignee:kex-y	29-22120 1 month ago	29-22120 1 month ago	39-24576 39 days
32570	ksenono author:ksenono	feat(Combinatorics/SimpleGraph): bipartite subgraphs and vertex-disjoint graphs for Konig's theorem	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-combinatorics new-contributor	22/0	Mathlib/Combinatorics/SimpleGraph/Bipartite.lean,Mathlib/Combinatorics/SimpleGraph/Subgraph.lean	2	19	['SnirBroshi', 'github-actions', 'jcommelin', 'ksenono', 'vlad902']	kmill assignee:kmill	28-84488 1 month ago	28-84488 1 month ago	81-34263 81 days
34053	christian-oudard author:christian-oudard	feat: Add error function (erf) and complementary error function (erfc)	## Summary I was doing some finance math and needed the Error Function, so I thought I'd contribute it. ### Main definitions * `Real.erf`: The error function, defined as `(2/√π) ∫₀ˣ e^(-t²) dt` * `Real.erfc`: The complementary error function, defined as `1 - erf x` ### Main results * `Real.erf_zero`: `erf 0 = 0` * `Real.erf_neg`: `erf` is an odd function: `erf (-x) = -erf x` * `Real.erf_tendsto_one`: `erf x → 1` as `x → ∞` * `Real.erf_tendsto_neg_one`: `erf x → -1` as `x → -∞` * `Real.erf_le_one`: `erf x ≤ 1` for all `x` * `Real.neg_one_le_erf`: `-1 ≤ erf x` for all `x` * `Real.deriv_erf`: `deriv erf x = (2/√π) * exp(-x²)` * `Real.differentiable_erf`: `erf` is differentiable * `Real.continuous_erf`: `erf` is continuous * `Real.strictMono_erf`: `erf` is strictly monotone Also adds `erf` to `docs/overview.yaml` under Special Functions. --- - [x] Builds successfully - [x] `lake exe runLinter` passes - [x] `lake exe mk_all --check` passes	awaiting-author t-analysis new-contributor	333/0	Mathlib.lean,Mathlib/Analysis/SpecialFunctions/Erf.lean,docs/overview.yaml	3	18	['SnirBroshi', 'christian-oudard', 'github-actions', 'j-loreaux', 'plp127']	j-loreaux assignee:j-loreaux	28-67174 1 month ago	29-17627 1 month ago	18-2435 18 days
33599	nielstron author:nielstron	feat(Computability/ContextFreeGrammar): closure under union	--- This PR picks up https://github.com/leanprover-community/mathlib4/pull/13514 and resolves the outstanding errors. - [ ] depends on: #33592 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR new-contributor t-computability	498/0	Mathlib/Computability/ContextFreeGrammar.lean	1	2	['github-actions', 'mathlib4-dependent-issues-bot']	YaelDillies assignee:YaelDillies	28-45028 1 month ago	47-53364 1 month ago	10-65787 10 days
33601	nielstron author:nielstron	feat(Computability/ContextFreeGrammar): Concatenation of CFGs is CFG	--- - [ ] depends on: #33599 - [ ] depends on: #33592 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR new-contributor t-computability	941/0	Mathlib/Computability/ContextFreeGrammar.lean	1	2	['github-actions', 'mathlib4-dependent-issues-bot']	nobody	28-44887 1 month ago	58-28750 1 month ago	0-412 6 minutes
33592	nielstron author:nielstron	feat(Computability/ContextFreeGrammar): mapping between two types of nonterminal symbols	This PR picks up https://github.com/leanprover-community/mathlib4/pull/15895 and resolves the failing lemma by redefining Good symbols. --- I checked that https://github.com/leanprover-community/mathlib4/pull/13514 builds correctly when based on this build. PR for that is #33599 This is my first contribution please let me know of any changes I should outline. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author new-contributor t-computability	158/0	Mathlib/Computability/ContextFreeGrammar.lean	1	27	['YaelDillies', 'github-actions', 'madvorak', 'nielstron']	nobody	28-42792 1 month ago	47-51679 1 month ago	10-68503 10 days
34191	IlPreteRosso author:IlPreteRosso	feat(Topology/Algebra/InfiniteSum): Discrete Convolution API 1st PR	Defines the very basics of the discrete convolution API. In analogy with [MeasureTheory.Convolution](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Analysis/Convolution.html#MeasureTheory.convolution). Main definitions include - `mulFiber`, `convolution`, `ConvolutionExists`, `ConvolutionExists.add_distrib`, `ConvolutionExistsAt.smul_convolution`, `mulFiber_swapEquiv`, `convolution_comm` RM: - The main docstring is as is - Next step is triple sum intrastrcutre + `assoc` theorems for convolution (long) Continues the work from #33411 and #33410 (splitting into shorter PRs, carries over the modifications from previous reviews)	t-topology new-contributor	277/0	Mathlib.lean,Mathlib/Topology/Algebra/InfiniteSum/DiscreteConvolution.lean	2	18	['IlPreteRosso', 'github-actions', 'j-loreaux']	PatrickMassot assignee:PatrickMassot	28-17194 1 month ago	28-17389 1 month ago	37-19045 37 days
34709	dennj author:dennj	feat(Analysis/ODE): add discrete Grönwall inequality	## Summary Add discrete Grönwall inequality to `Mathlib/Analysis/ODE/DiscreteGronwall.lean` Provides bounds for recurrence inequalities of the form `u(n+1) ≤ c(n) * u(n) + b(n)` ### Main results - `discrete_gronwall_prod_general`: Product form working over any linearly ordered commutative ring - `prod_one_add_Ico_mono`: Auxiliary lemma for product comparisons over subintervals - `discrete_gronwall`: Classical exponential bound `u(n) ≤ (u(n₀) + ∑ b(k)) * exp(∑ c(i))` (ℝ-specific) - `discrete_gronwall_Ico`: Uniform bound over a finite interval (ℝ-specific) ## Related work Complements the continuous Grönwall inequality in `Mathlib.Analysis.ODE.Gronwall` ## References * Grönwall, T. H. (1919). "Note on the derivatives with respect to a parameter of the solutions of a system of differential equations". Annals of Mathematics, 20(4), 292–296.	t-analysis new-contributor	174/0	Mathlib.lean,Mathlib/Analysis/ODE/DiscreteGronwall.lean	2	1	['github-actions']	ADedecker assignee:ADedecker	26-74812 26 days ago	30-64183 1 month ago	30-64221 30 days
34394	Citronhat author:Citronhat	feat(Algebra/Order/Ring): add constructors for linear ordered rings	Add constructors for ordered rings from `mul_nonneg` / `mul_pos` that derive `ZeroLEOneClass` from a linear order.	awaiting-author t-algebra new-contributor label:t-algebra$	31/14	Mathlib/Algebra/Order/Ring/Defs.lean,Mathlib/RingTheory/HahnSeries/Lex.lean	2	6	['Citronhat', 'Vierkantor', 'github-actions', 'leanprover-radar']	Vierkantor assignee:Vierkantor	26-37249 26 days ago	26-37249 26 days ago	12-25418 12 days
34182	IlPreteRosso author:IlPreteRosso	feat(Data/Finsupp/Single, Data/Finsupp/Indicator): Add set_indicator_singleton, indicator_singleton; golfed single_eq_set_indicator, single_eq_indicator	[Mathlib.Data.Finsupp.Single](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Data/Finsupp/Single.html#Finsupp.single) - Add `set_indicator_singleton`, golfed `single_eq_set_indicator` [Mathlib.Data.Finsupp.Indicator](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Data/Finsupp/Indicator.html#Finsupp.indicator_apply) - Add `indicator_singleton`, golfed `single_eq_indicator` Continues the work from #34095	new-contributor t-data large-import	17/17	Mathlib/Data/Finsupp/Indicator.lean,Mathlib/Data/Finsupp/Single.lean	2	29	['IlPreteRosso', 'eric-wieser', 'github-actions', 'mathlib-bors', 'urkud']	eric-wieser and urkud assignee:urkud assignee:eric-wieser	26-18105 26 days ago	42-24432 1 month ago	42-71088 42 days
33493	michelsol author:michelsol	feat(RingTheory/Polynomial): An explicit formula for the Chebyshev polynomials of the first kind	Adds the following explicit formula on the Chebyshev polynomial of the first kind of order n. ${ T_{n}(x)\ =\ \sum \limits _{k=0}^{\lfloor {\frac {n}{2}}\rfloor } {\binom {n}{2k}} \left(\ X^{2}-1\ \right)^{k}\ X^{n-2k}}$ This explicit formula can be found [here](https://en.wikipedia.org/wiki/Chebyshev_polynomials#Explicit_expressions). There is a proof using complex numbers but it only works if the ring R = ℂ. The proof here is by induction and works in a commutative ring R. Mathlib seems to extend the definition of Chebyshev polynomials for $n \in \mathbb{Z}$ but this would make the formula more cumbersome with `n.natAbs` in place of `n`'s, so I expressed it on `n : ℕ` directly. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author new-contributor t-ring-theory	51/1	Mathlib/RingTheory/Polynomial/Chebyshev.lean	1	8	['YuvalFilmus', 'erdOne', 'github-actions', 'metakunt', 'michelsol']	chrisflav assignee:chrisflav	24-73488 24 days ago	24-73488 24 days ago	35-16105 35 days
34815	Deep0Thinking author:Deep0Thinking	feat(Analysis/SpecialFunctions/ImproperIntegrals): Frullani integral	- [ ] depends on: #34966 --- Add a proof of Frullani integral. Main theorems: - `Frullani.integral_Ioi` - `IntegrableOn.tendsto_integral_Ioi` - `exists_integral_div_eq_mul_log` Supporting lemmas: - `Frullani.comp_mul_left_div` - `Frullani.intervalIntegrable_div` - `Frullani.exists_integral_div_eq_mul_log` - `Ioi_diff_Ioc` - `ContinuousOn.comp_mul_left_div`, `ContinuousOn.comp_mul_right_div` - `ContinuousOn.comp_mul_left`, `ContinuousOn.comp_mul_right` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR awaiting-author t-analysis new-contributor large-import	270/2	Mathlib/Analysis/SpecialFunctions/ImproperIntegrals.lean,Mathlib/MeasureTheory/Integral/IntegralEqImproper.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/MeanValue.lean,Mathlib/Order/Interval/Set/LinearOrder.lean,Mathlib/Topology/Algebra/GroupWithZero.lean,Mathlib/Topology/Algebra/Monoid.lean	6	6	['CoolRmal', 'Deep0Thinking', 'github-actions', 'mathlib-dependent-issues', 'sgouezel']	nobody	24-57203 24 days ago	24-57204 24 days ago	1-48681 1 day
34093	YellPika author:YellPika	feat(Order/OmegaCompletePartialOrder): add `OmegaCompletePartialOrder` instance for `Option` with basic `ωScottContinuous` lemmas	--- - [x] depends on: #33941 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-order new-contributor	297/0	Mathlib.lean,Mathlib/Data/Option/Order.lean,Mathlib/Order/Monotone/Basic.lean,Mathlib/Order/OmegaCompletePartialOrder.lean	4	5	['YellPika', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts']	pechersky assignee:pechersky	23-74798 23 days ago	28-58908 1 month ago	28-60142 28 days
26985	agjftucker author:agjftucker	feat(Analysis/Calculus/ImplicitFunction): define implicitFunctionOfProdDomain	This PR continues the work from #16743. Original PR: https://github.com/leanprover-community/mathlib4/pull/16743 --- - [x] depends on: #28352 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-analysis new-contributor	269/157	Mathlib.lean,Mathlib/Analysis/Calculus/Implicit.lean,Mathlib/Analysis/Calculus/ImplicitContDiff.lean,Mathlib/Analysis/Calculus/ImplicitFunction/ProdDomain.lean	4	27	['agjftucker', 'github-actions', 'j-loreaux', 'mathlib-bors', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'winstonyin']	hrmacbeth assignee:hrmacbeth	22-50257 22 days ago	22-50257 22 days ago	90-69470 90 days
32744	NoneMore author:NoneMore	feat(ModelTheory/Definablity): add `DefinableFun` definition and lemmas	This PR adds two basic shapes of definable sets and `DefinableFun` definition with relevant lemmas. The main result is `Set.Definable.preimage_of_map` asserting that the preimage of a definable set under a definable map is definable. There are also some tool lemmas derived by the preimage lemma. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-logic new-contributor	147/0	Mathlib/ModelTheory/Definability.lean	1	59	['NoneMore', 'github-actions', 'mathlib4-merge-conflict-bot', 'staroperator']	awainverse assignee:awainverse	22-44293 22 days ago	54-54013 1 month ago	82-53214 82 days
26986	WangYiran01 author:WangYiran01	feat(Partition): add bijection for partitions with max part ≤ r	This PR adds a new theorem `partition_max_equals_bound` to `Mathlib.Combinatorics.Enumerative.Partition`. It constructs a bijection between: - The set of partitions of `n` in which `r ∈ π.parts` and all parts are `≤ r`, and - The set of partitions of `n - r` whose largest part is at most `r`. This provides a constructive proof via removing/adding `r` from/to the partition multiset, in line with classical enumerative combinatorics. Contributed by Yiran Wang.	awaiting-author merge-conflict t-combinatorics new-contributor	92/0	Mathlib/Combinatorics/Enumerative/Partition/Basic.lean,Mathlib/Data/Multiset/Lattice.lean	2	20	['WangYiran01', 'github-actions', 'jcommelin', 'kckennylau', 'kim-em', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot']	b-mehta assignee:b-mehta	22-21962 22 days ago	22-21963 22 days ago	120-67067 120 days
26168	oliver-butterley author:oliver-butterley	feat(MeasureTheory.VectorMeasure): variation defined as a supremum is equal to variation defined using the Hahn-Jordan decomposition	Add `signedMeasure_totalVariation_eq`: if `μ` is a `SignedMeasure` then variation defined as a supremum is equal to variation defined using the Hahn-Jordan decomposition. Co-authored-by: @yoh-tanimoto - [ ] depends on: #26165 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-measure-probability new-contributor	916/0	Mathlib.lean,Mathlib/MeasureTheory/VectorMeasure/Integral.lean,Mathlib/MeasureTheory/VectorMeasure/Variation/Defs.lean,Mathlib/MeasureTheory/VectorMeasure/Variation/Equiv.lean,Mathlib/MeasureTheory/VectorMeasure/Variation/Lemmas.lean	5	4	['github-actions', 'mathlib-merge-conflicts', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	22-2951 22 days ago	22-2952 22 days ago	15-65390 15 days
33463	khwilson author:khwilson	feat(Mathlib/Analysis/Polynomial/MahlerMeasure): Mahler Measure for other rings	Define `mahlerMeasure'` which allows you specify a norm preserving map `v` from any `NormedRing A` (or more general) to `ℂ`. Also provide wrappers around the main `mahlerMeasure` lemmas that are used for estimation. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-analysis new-contributor	97/3	Mathlib/Analysis/Polynomial/MahlerMeasure.lean,Mathlib/NumberTheory/MahlerMeasure.lean	2	21	['github-actions', 'j-loreaux', 'khwilson', 'plp127', 'vlad902']	nobody	21-85693 21 days ago	22-1516 22 days ago	40-12322 40 days
34481	DAE123456 author:DAE123456	feat: Ore's Theorem	Ore Theorem : Let G be a graph of order n ≥ 3 that satisfies the Ore property. Then G has a Hamilton cycle.	t-combinatorics new-contributor	3372/0	Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Ore.lean	2	25	['DAE123456', 'LLaurance', 'Ruben-VandeVelde', 'YaelDillies', 'github-actions', 'kim-em', 'tb65536', 'vlad902']	b-mehta assignee:b-mehta	21-74644 21 days ago	34-18845 1 month ago	34-50632 34 days
34722	GrigorenkoPV author:GrigorenkoPV	feat(Data/Finset/RangeDistance): add	--- Rebase of https://github.com/leanprover-community/mathlib4/pull/26347 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	new-contributor t-data	34/0	Mathlib.lean,Mathlib/Algebra/Order/Group/Unbundled/Abs.lean,Mathlib/Data/Finset/RangeDistance.lean	3	4	['GrigorenkoPV', 'github-actions', 'joneugster', 'plp127']	TwoFX assignee:TwoFX	21-74640 21 days ago	25-31833 25 days ago	30-33097 30 days
35122	Marygold-Dusk author:Marygold-Dusk	feat: define C^n submersions	This PR defines submersions between C^n manifolds. In the infinite-dimensional setting, submersions are defined via local normal forms rather than surjectivity of the mfderiv. A map f is a submersion at x if, in suitable charts around x and f x, it has the form (u, v) ↦ u after identifying the model space with a product. We prove a few basic properties: - being a submersion is a local property, - products of submersions are submersions, - the set of submersed points is open Future PRs will prove that submersions are C^n and deduce equivalence with the standard definition in finite dimensions. From the path towards the regular value theorem. This file was developed under the supervision of Michael Rothgang. Co-authored-by: Michael Rothgang --- Most of the design is analogues to submersions.	t-differential-geometry new-contributor	596/0	Mathlib.lean,Mathlib/Geometry/Manifold/Submersion.lean	2	2	['github-actions']	grunweg assignee:grunweg	21-24660 21 days ago	21-41513 21 days ago	21-41569 21 days
32845	jonasvanderschaaf author:jonasvanderschaaf	feat(CategoryTheory): `GrothendieckTopology.yoneda` preserves certain (co)limits	We prove that if every `J`-sheaf preserves limits of shape `Kᵒᵖ`, then `J.yoneda` preserves colimits of shape `K`, and the dual statement. We specialize to the case of finite products, and deduce that the inclusion of light profinite sets in light condensed sets preserves finite coproducts From [LeanCondensed](https://github.com/dagurtomas/LeanCondensed) --- Co-authored-by: Dagur Asgeirsson [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-category-theory new-contributor t-condensed large-import	107/5	Mathlib.lean,Mathlib/CategoryTheory/Limits/Preserves/Shapes/Products.lean,Mathlib/CategoryTheory/Sites/PreservesLimits.lean,Mathlib/Condensed/Functors.lean,Mathlib/Condensed/Light/Functors.lean	5	5	['github-actions', 'jonasvanderschaaf', 'robin-carlier']	nobody	21-17625 21 days ago	33-45057 1 month ago	8-53243 8 days
33969	goliath-klein author:goliath-klein	refactor(PiTensorProduct/{InjectiveNorm, ProjectiveNorm}): Currently, injectiveSeminorm = projectiveSeminorm	WIP / RFC! Arguably, `injectiveSeminorm` should be re-defined in Mathlib. See #34137 and [Zulip](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/injectiveSeminorm/with/568798261) for context. In this file, we collect some results about the current definition and a possible alternative. Contents: * A theorem `injectiveSeminorm_eq_projectiveSeminorm` formalizing the equality of the current definitions. However, I think it is unlikely that keeping the alternative characterization would be worth the effort. The interesting direction `(L2') ≤ (L1)` follows from `norm_eval_le_projectiveSeminorm` which is still present. The converse direction is [somewhat tautological](https://github.com/leanprover-community/mathlib4/pull/34137). A proof of `(L2) = (L1)` (probably requiring Hahn-Banach) might be more interesting. * A preliminary implementation of the injective seminorm as commonly understood. * Sufficient conditions for the multiplicativity property `‖⨂ m i‖_∧ = ∏ ‖m i‖` to hold. This implements a TBD item. --- Co-authored-by: Davood H. H. Tehrani [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP merge-conflict t-analysis new-contributor large-import	774/387	Mathlib.lean,Mathlib/Analysis/Normed/Module/Dual.lean,Mathlib/Analysis/Normed/Module/HahnBanach.lean,Mathlib/Analysis/Normed/Module/PiTensorProduct/InjectiveSeminorm.lean,Mathlib/Analysis/Normed/Module/PiTensorProduct/LeastReasonable.lean,Mathlib/Analysis/Normed/Module/PiTensorProduct/ProjectiveSeminorm.lean,Mathlib/Analysis/Normed/Operator/Basic.lean,Mathlib/LinearAlgebra/PiTensorProduct.lean	8	3	['github-actions', 'goliath-klein', 'mathlib-merge-conflicts']	nobody	21-5312 21 days ago	21-5313 21 days ago	0-23 23 seconds
33032	ksenono author:ksenono	feat(Combinatorics/SimpleGraph): Konig’s theorem on bipartite graphs	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-combinatorics new-contributor	832/251	Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Bipartite.lean,Mathlib/Combinatorics/SimpleGraph/Clique.lean,Mathlib/Combinatorics/SimpleGraph/DegreeSum.lean,Mathlib/Combinatorics/SimpleGraph/Konig/Auxillary.lean,Mathlib/Combinatorics/SimpleGraph/Konig/Konig.lean,Mathlib/Combinatorics/SimpleGraph/Konig/KonigFin.lean,Mathlib/Combinatorics/SimpleGraph/Matching.lean,Mathlib/Combinatorics/SimpleGraph/Subgraph.lean,Mathlib/Combinatorics/SimpleGraph/VertexCover.lean,Mathlib/SetTheory/Cardinal/Arithmetic.lean,Mathlib/SetTheory/Cardinal/Basic.lean	12	8	['SnirBroshi', 'github-actions', 'ksenono', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'vlad902']	nobody	19-68845 19 days ago	58-44954 1 month ago	0-1252 20 minutes
31662	edwin1729 author:edwin1729	feat(Topology/Order): topological basis of scott topology on Complete…	…PartialOrder --- [Zulip discussion](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/.3E.20Algebraic.20complete.20partial.20order.20and.20domain.20theory/with/536359313) for this PR. (1/2) PRs in domain theory, proving that scott topologies over Algebraic DCPOs (`CompletePartialOrder`) are sober. The main reference is [Reneta, Duality in Domain Theory](https://alyata.github.io/documents/duality_domain_theory.pdf). But the statements can also be found in the canonical text [Abramsky and Jung](https://www.cs.ox.ac.uk/people/samson.abramsky/handbook.pdf) This first PR proves two prerequisites, namely: - the specialization order induced by the scott topology corresponds to the existing order of the DCPO. Prop 3.1.5 in [Duality in Domain Theory](https://alyata.github.io/documents/duality_domain_theory.pdf) and Prop 2.3.2(1) in [Abramsky and Jung](https://www.cs.ox.ac.uk/people/samson.abramsky/handbook.pdf) - the upward closures of compact elements of the DCPO form a topological basis for the Scott Topology. Prop 3.5.2 in [Duality in Domain Theory](https://alyata.github.io/documents/duality_domain_theory.pdf) and Prop 2.3.6(2) in [Abramsky and Jung](https://www.cs.ox.ac.uk/people/samson.abramsky/handbook.pdf) - [ ] depends on: #33061 The next PR is here: #31670 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-topology new-contributor	281/1	Mathlib.lean,Mathlib/Topology/Order/ScottTopology.lean,Mathlib/Topology/Order/ScottTopologyDCPO.lean,docs/references.bib	4	42	['b-mehta', 'edwin1729', 'github-actions', 'mathlib-merge-conflicts', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'plp127']	b-mehta assignee:b-mehta	19-52177 19 days ago	19-52178 19 days ago	13-48937 13 days
34159	wangying11123 author:wangying11123	feat(Geometry/Euclidean/Similarity): Add Triangle similarity on oangle	Add theorems about triangles similarity on oangle	awaiting-author t-euclidean-geometry new-contributor	154/1	Mathlib/Geometry/Euclidean/Similarity.lean	1	8	['LLaurance', 'github-actions', 'jsm28', 'wangying11123']	jsm28 assignee:jsm28	19-32612 19 days ago	19-79841 19 days ago	7-49555 7 days
32807	WilliamCoram author:WilliamCoram	feat: Define the Gauss norm for MvPowerSeries	We adjust the current definition for Gauss norm on power series to work for multivariate power series. If this seems acceptable I can refactor the single variable case. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	new-contributor t-ring-theory	124/0	Mathlib.lean,Mathlib/RingTheory/MvPowerSeries/GaussNorm.lean	2	25	['WilliamCoram', 'erdOne', 'fbarroero', 'github-actions', 'mathlib4-merge-conflict-bot', 'vihdzp']	alreadydone assignee:alreadydone	19-28678 19 days ago	23-19707 23 days ago	51-15086 51 days
31366	FaffyWaffles author:FaffyWaffles	feat(Analysis/SpecialFunctions/StirlingRobbins): Robbins' sharp stepwise bound for stirlingSeq	Introduces `Mathlib.Analysis.SpecialFunctions.StirlingRobbins`, proving Robbins' sharp stepwise bound for the Stirling sequence. * Main theorem: `log_stirlingSeq_diff_le` * Improves the existing bound `1/(4k^2)` to the sharp `1/(12k(k+1))` * Adds helper lemmas on summability and geometric bounds * Complements `Stirling.lean` References: - https://leanprover-community.github.io/mathlib4_docs/Mathlib/Analysis/SpecialFunctions/Stirling.html - Robbins (1955), A Remark on Stirling’s Formula --- Note for Transparency: Assistance provided by AI tools (Claude and Aristotle) for drafting, text, and structure. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-analysis new-contributor	64/5	Mathlib/Analysis/SpecialFunctions/Stirling.lean	1	17	['FaffyWaffles', 'github-actions', 'j-loreaux', 'mathlib4-merge-conflict-bot', 'tb65536']	nobody	19-11522 19 days ago	98-86233 3 months ago	4-57241 4 days
35144	daniel-carranza author:daniel-carranza	feat(CategoryTheory/Enriched): tensor product of enriched categories	For a braided monoidal category `V`, defines the tensor product of `V`-categories `C` and `D`, and shows that the type of `V`-functors out of the tensor product `C \times D` is equivalent to the type of "enriched bifunctors" `EnrichedBifunctor V C D`. --- This work originates from infinity-cosmos project, where it is used to formalize the notion of cotensors in an enriched category. There are some additional coherence lemmas in a braided monoidal category which have been added. Currently, line 209 violates the style guideline that terminal simp calls should not be squeezed. When I tried to replace this with a single `simp`, I get an error message: `maximum recursion depth has been reached`. Any suggestions (either with this or anything else) are greatly appreciated - thank you! [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-category-theory new-contributor infinity-cosmos	333/0	Mathlib.lean,Mathlib/CategoryTheory/Enriched/TensorProductCategory.lean,Mathlib/CategoryTheory/Monoidal/Braided/Basic.lean	3	11	['daniel-carranza', 'emilyriehl', 'github-actions', 'robin-carlier']	nobody	18-20700 18 days ago	19-41851 19 days ago	1-52648 1 day
33050	mkaratarakis author:mkaratarakis	feat: lemmas for the analytic part of the proof of the Gelfond–Schneider theorem	Lemmas missing for the formalisation of the proof of the Gelfond–Schneider theorem --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP t-number-theory new-contributor	238/0	Mathlib.lean,Mathlib/Analysis/Analytic/Basic.lean,Mathlib/Analysis/Analytic/Order.lean,Mathlib/Analysis/Complex/CauchyIntegral.lean,Mathlib/NumberTheory/Transcendental/AnalyticPart.lean,Mathlib/NumberTheory/Transcendental/AnalyticPart2.lean	6	113	['SnirBroshi', 'github-actions', 'j-loreaux', 'mkaratarakis', 'riccardobrasca', 'vihdzp']	riccardobrasca assignee:riccardobrasca	18-14992 18 days ago	21-29470 21 days ago	12-11420 12 days
33217	Blackfeather007 author:Blackfeather007	feat(Algebra): define associated graded structure for abelian group	In this PR we define the associated graded structure for abelian group when given a filtration and only give some basic lemmas about it. --- migrated from https://github.com/leanprover-community/mathlib4/pull/26857	awaiting-author new-contributor t-ring-theory	144/0	Mathlib.lean,Mathlib/RingTheory/FilteredAlgebra/AssociatedGraded.lean	2	5	['erdOne', 'github-actions', 'urkud']	erdOne assignee:erdOne	17-74612 17 days ago	67-2608 2 months ago	4-62376 4 days
33281	michelsol author:michelsol	feat(Analysis/SpecialFunctions/Integrals): integral of 1/sqrt(1-x^2) and its integrability.	Add the integral of the derivative of arcsin and its integrability. --- - [ ] depends on: #33280 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-analysis new-contributor	59/0	Mathlib/Analysis/SpecialFunctions/Integrability/Basic.lean,Mathlib/Analysis/SpecialFunctions/Integrals/Basic.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/FundThmCalculus.lean	3	3	['github-actions', 'mathlib-dependent-issues', 'mathlib4-merge-conflict-bot']	nobody	17-43299 17 days ago	17-43301 17 days ago	0-2872 47 minutes
29777	yuanyi-350 author:yuanyi-350	feat(Functional Analysis): closed Range Theorem	- [ ] depends on: #29151 [Corollary of Hahn-Banach theorem] - [ ] depends on: #29776 [refactor ContinuousLinearMap.isOpenMap by separating it into sublemmas] --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP blocked-by-other-PR awaiting-author merge-conflict t-analysis new-contributor	237/25	Mathlib/Analysis/LocallyConvex/Separation.lean,Mathlib/Analysis/Normed/Operator/Banach.lean,Mathlib/Analysis/Normed/Operator/ClosedRange.lean,Mathlib/Analysis/RCLike/Lemmas.lean,Mathlib/Topology/Order/OrderClosed.lean	5	5	['github-actions', 'mathlib-merge-conflicts', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	faenuccio assignee:faenuccio	17-12484 17 days ago	17-12485 17 days ago	0-634 10 minutes
29151	yuanyi-350 author:yuanyi-350	feat: Corollary of Hahn–Banach theorem	In this PR, I have proved [Rudin, Functional Analysis (Theorem 3.7)][rudin1991] which is a step in proving the Closed Range Theorem. Also, I have added tags for the corresponding theorems in Rudin to mathlib. 3.7 Theorem. Suppose B is a convex, balanced, closed set in a locally convex space $X, x_0 \in X$, but $x_0 \notin B$. Then there exists $\Lambda \in X^$ such that $\|\Lambda x\| \leq 1$ for all $x \in B$, but $\Lambda x_0>1$ proof. Since $B$ is closed and convex, we can apply (b) of Theorem 3.4, with $A=\{ x_0 \}$ , to obtain $\Lambda_1 \in X^$ such that $\Lambda_1 x_0=r e^{i \theta}$ lies outside the closure $K$ of $\Lambda_1(B)$. Since $B$ is balanced, so is $K$. Hence there exists $s, 0 List.Vector.* - ... Deletions: - Nat.bit1_add_bit1 - ... Any other comments you want to keep out of the PR commit should go below the `---`, and placed outside this HTML comment, or else they will be invisible to reviewers. If this PR depends on other PRs, please list them below this comment, using the following format: - [ ] depends on: #xyz [optional extra text] --> [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-analysis new-contributor large-import	70/1	Mathlib/Analysis/LocallyConvex/Separation.lean,Mathlib/Analysis/RCLike/Lemmas.lean,Mathlib/Topology/Order/OrderClosed.lean	3	17	['faenuccio', 'fpvandoorn', 'github-actions', 'mathlib-merge-conflicts', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'mcdoll', 'themathqueen', 'yuanyi-350']	faenuccio assignee:faenuccio	17-8107 17 days ago	17-8108 17 days ago	21-29486 21 days
32918	michelsol author:michelsol	feat: define `supEdist` and `supDist`	Create a new file Topology.MetricSpace.SupDistance and define the supremal distance in (extended) metric spaces. The defined `supEdist` and `supDist` will have similar theory to the already existing `infEdist` and `infDist`. The motivation is to be able to define the radius of a minimal bounding sphere as the infimum of the supDist later. [zulip discussion here](https://leanprover.zulipchat.com/#narrow/channel/116395-maths/topic/Formalizing.20Jung's.20theorem.20and.20minimal.20bounding.20spheres)	merge-conflict t-topology new-contributor	75/0	Mathlib.lean,Mathlib/Topology/MetricSpace/SupDistance.lean	2	5	['github-actions', 'mathlib4-merge-conflict-bot', 'michelsol', 'urkud']	RemyDegenne assignee:RemyDegenne	16-13398 16 days ago	58-5783 1 month ago	21-5159 21 days
35017	robo7179 author:robo7179	feat(Combinatorics/SimpleGraph/Acyclic): add every nontrivial tree has atleast two leaves	Added two theorems to prove that every non trivial tree has atleast two leaves (one in Finite the other in Acyclic). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-combinatorics new-contributor	94/0	Mathlib/Combinatorics/SimpleGraph/Acyclic.lean,Mathlib/Combinatorics/SimpleGraph/Finite.lean	2	24	['IvanRenison', 'SnirBroshi', 'github-actions', 'robo7179']	nobody	16-2258 16 days ago	22-13936 22 days ago	23-34605 23 days
34578	dennj author:dennj	feat: define Boolean circuits over abstract gate families	This PR introduces a foundation for Boolean circuits parameterized by abstract gate families. ## Main definitions - `GateEval`: typeclass for gate families with Boolean semantics - `GateHom`: arity-preserving maps between gate families - `Circuit`: inductive type representing circuit syntax trees - `AC0Gate`, `ACC0Gate`, `TC0Gate`: standard complexity-theoretic gate bases ## Design notes The key design choice is to keep syntax (gate labels `G : Nat → Type`) separate from semantics (`GateEval.eval`), allowing users to define custom gate families (e.g., MAJ, XOR, arbitrary threshold gates) without modifying core definitions. ### Tree vs DAG representation We evaluated two approaches for circuit representation: 1. Tree-based (this PR): Circuits as inductive syntax trees 2. DAG-based: Circuits as lists of gates with index-based references We chose tree-based circuits because: - Compositionality: Easy to build circuits via `gate g (fun i => subcircuit i)` - Type safety: Arity-indexed gates (`G : Nat → Type`) catch errors at compile time - Manipulation: Natural support for `mapGate`, `subst`, `mapInputs` - Mathlib philosophy: Aligns with structural/compositional reasoning patterns For use cases requiring explicit sharing (complexity analysis, evaluation efficiency), a separate `DAG` type can be added later with proven equivalence via `Circuit.toDAG`. The current representation serves as a minimal foundation for size/depth measures, circuit families, and complexity classes (AC0, ACC0, TC0). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	new-contributor t-computability	919/0	Mathlib.lean,Mathlib/Computability/Circuit/Basic.lean,Mathlib/Computability/Formula/Basic.lean,Mathlib/Computability/Gate.lean	4	18	['LLaurance', 'YuvalFilmus', 'dennj', 'github-actions']	nobody	15-68262 15 days ago	15-68262 15 days ago	23-45662 23 days
26413	michaellee94 author:michaellee94	feat: existence of maximal solutions for ODEs meeting Picard-Lindelöf conditions	Add existence proof for maximal solution of ODE using Picard-Lindelöf and a uniqueness theorem using Grönwall's lemma. --- - [x] depends on: #26382 - [ ] depends on: #29186 - [ ] depends on: #35043 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR merge-conflict t-analysis new-contributor	1300/431	Mathlib.lean,Mathlib/Analysis/ODE/Basic.lean,Mathlib/Analysis/ODE/ExistUnique.lean,Mathlib/Analysis/ODE/Gronwall.lean,Mathlib/Analysis/ODE/MaximalSolution.lean,Mathlib/Analysis/ODE/PicardLindelof.lean,Mathlib/Analysis/ODE/Transform.lean,Mathlib/Geometry/Manifold/IntegralCurve/Basic.lean,Mathlib/Geometry/Manifold/IntegralCurve/ExistUnique.lean,Mathlib/Geometry/Manifold/IntegralCurve/Transform.lean,Mathlib/Geometry/Manifold/IntegralCurve/UniformTime.lean,docs/1000.yaml,docs/undergrad.yaml	13	95	['botbaki-review', 'github-actions', 'grunweg', 'leanprover-community-bot-assistant', 'mathlib-merge-conflicts', 'mathlib4-dependent-issues-bot', 'michaellee94', 'winstonyin']	nobody	15-40933 15 days ago	15-40935 15 days ago	0-5139 1 hour
33712	wangying11123 author:wangying11123	feat(Geometry/Euclidean/Angle/Unoriented/Projection): Add sameray_orthogonalProjection_vsub_of_angle_lt	Add sameray_orthogonalProjection_vsub_of_angle_lt `sameray_orthogonalProjection_vsub_of_angle_lt` When an angle is acute, the vector to the orthogonal projection lies in the same ray as the given direction vector.	awaiting-author t-euclidean-geometry new-contributor	20/0	Mathlib/Geometry/Euclidean/Angle/Unoriented/Projection.lean	1	4	['JovanGerb', 'github-actions', 'j-loreaux']	JovanGerb assignee:JovanGerb	15-23229 15 days ago	15-23329 15 days ago	41-14005 41 days
33786	hdmkindom author:hdmkindom	feat(Analysis/Matrix): add Jacobian matrix for matrix-valued functions	This PR introduces the Jacobian matrix for matrix-valued functions `F : Matrix m n ℝ → Matrix p q ℝ`. The Jacobian matrix `jacobianMatrix F X` at point `X` is indexed by `(p × q) × (m × n)`, where each entry represents the partial derivative with respect to a basis element. To handle instance-mismatch issues with matrix norms, we use local Frobenius norm instances. mkdir Analysis/Matrix/Jacobian.lean ## Main definitions - `jacobianMatrix F X`: The Jacobian matrix at point `X`, defined by `jacobianMatrix F X (i, k) (j, l) = (fderiv ℝ F X (Matrix.single j l 1)) i k` ## Main theorems - `fderiv_eq_jacobian_mul`: Express the Fréchet derivative as a contraction with the Jacobian - `jacobianMatrix_comp`: Chain rule for Jacobian matrices - `jacobianMatrix_linear`, `jacobianMatrix_id`, `jacobianMatrix_const`: Basic properties - `jacobianMatrix_add`, `jacobianMatrix_smul`: Linearity properties	awaiting-author t-analysis new-contributor	219/0	Mathlib.lean,Mathlib/Analysis/Matrix/Jacobian.lean	2	11	['erdOne', 'github-actions', 'jcommelin']	sgouezel assignee:sgouezel	15-22877 15 days ago	15-23631 15 days ago	39-35999 39 days
30667	FrederickPu author:FrederickPu	feat(‎Mathlib/Algebra/Group/Subgroup/Pointwise): subgroup mul	Title: feat: pointwise products for subgroups Description: showed the point-wise product of disjoint subgroups is equivalent to their Cartesian product. Based on https://leanprover.zulipchat.com/#narrow/channel/113488-general/topic/useful.20group.20theory.20lemmas/with/546738566. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-algebra new-contributor label:t-algebra$	28/0	Mathlib/Algebra/Group/Subgroup/Pointwise.lean	1	23	['FrederickPu', 'eric-wieser', 'github-actions', 'plp127', 'tb65536']	nobody	15-21738 15 days ago	16-2001 16 days ago	16-48262 16 days
35448	mathlib-splicebot author:mathlib-splicebot	chore(Mathlib/Tactic/Linter/GlobalSyntax.lean): automated extraction	This PR was automatically created from a review comment on PR #34019.	new-contributor t-linter	138/0	Mathlib/Tactic/Linter/GlobalSyntax.lean	1	2	['github-actions']	nobody	15-19388 15 days ago	15-19388 15 days ago	0-0 0 seconds
33793	LTolDe author:LTolDe	feat(MeasureTheory/Constructions/Polish/Basic): add lemma AnalyticSet.inter_nonempty_of_nowhereMeagre	add lemma AnalyticSet.inter_nonempty_of_nowhereMeagre, the main ingredient for the proof of the Effros' Theorem, see [#mathlib4 > Effros Theorem](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Effros.20Theorem/with/566543328) introduce definition of a nowhere meagre set --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-measure-probability new-contributor	37/0	Mathlib/MeasureTheory/Constructions/Polish/Basic.lean,Mathlib/Order/Filter/Basic.lean,Mathlib/Topology/GDelta/Basic.lean	3	8	['MichaelStollBayreuth', 'erdOne', 'github-actions', 'j-loreaux']	kex-y assignee:kex-y	15-17495 15 days ago	15-17701 15 days ago	39-9592 39 days
34851	dennj author:dennj	feat(Data/Matrix/Mul): add diagonal and transpose lemmas for vector operations	This adds three lemmas for matrix-vector operations that serve as foundational support for future ML formalization: - `vecMul_diagonal_dotProduct`: weighted inner product `x ᵥ* diagonal d ⬝ᵥ y = ∑ i, d i * x i * y i` - `dotProduct_transpose_mulVec`: bilinear form symmetry `x ⬝ᵥ Aᵀ ᵥ y = y ⬝ᵥ A ᵥ x` - `mul_diagonal_mulVec`: column-weighted sum `(A * diagonal d) ᵥ x = ∑ i, (d i x i) • A.col i` These are basic linear algebra identities involving diagonal matrices and vector operations that appear frequently in machine learning contexts (weighted inner products, attention mechanisms, feature scaling, diagonal preconditioning).	new-contributor t-data	22/0	Mathlib/Data/Matrix/Mul.lean	1	5	['dennj', 'eric-wieser', 'github-actions', 'themathqueen']	pechersky assignee:pechersky	14-80822 14 days ago	28-3830 1 month ago	28-3872 28 days
28546	Sfgangloff author:Sfgangloff	feat(SymbolicDynamics): basic setup of Zd, full shift, cylinders, pat…	This PR adds a group-generic foundation for symbolic dynamics over an arbitrary group `G`, together with convenient specializations for `ℤ` and `ℤ^d`. Summary of additions: - Full shift and shift action - `abbrev FullShift (A G) := G → A` (inherits product topology from the Π-type). - Right shift `shift g x` with convention `(shift g x) h = x (h * g)`. - Cylinders and topology - `cylinder U x : Set (G → A)` for finite `U : Finset G`. - Cylinders are open under `[DiscreteTopology A]`; with a finite alphabet they are also closed. - Equality with dependent products: `cylinder U x = Set.pi (↑U) (fun i => ({x i} : Set A))`, enabling use of the `Set.pi` API. - Patterns, occurrences, and subshifts - `Pattern A G` with finite `support : Finset G` and `data : support → A`. - `Pattern.occursIn p x g` (occurrence at translate `g`) and the expected shift law. - `forbids F` and `Subshift A G` (closed, shift-invariant subsets). - `FixedSupport A G U` with an equivalence to `(U → A)` to obtain finiteness. - Language on finite shapes and counting - `languageOn X U`, `languageCardOn X U`, and `patternCountOn Y U`. - Entropy along a shape sequence - `limsupAtTop` (as an `sInf` of eventual upper bounds). - `entropyAlong X F hF := limsup (log (patternCountOn X (F n) + 1) / \|F n\|)` for any nonempty finite shapes `F : ℕ → Finset G` (the `+ 1` avoids `log 0`). - Specializations - `IntShapes`: segments `[-n,n]` on `Multiplicative ℤ`, with `entropy_Z`. - `ZdShapes`: boxes `[-n,n]^d` on `ℤ^d` (as functions `Fin d → ℤ`), with `entropy_Zd`. Mathematical remarks: - The API is shape-parametric: entropy is defined along user-provided finite shapes. - On amenable groups, using a Følner sequence yields a canonical value (Ornstein–Weiss). This PR does not assume amenability; the family of shapes is an explicit input. Motivation: Provide a clean, reusable base for symbolic dynamics on groups in mathlib. Future work: - Add a Følner predicate and prove shape-independence / limit existence on amenable groups. - Expand the `ℤ`/`ℤ^d` toolkit (alternative shapes, mixing, factors). - Develop 1D theory and, longer-term, multidimensional SFT results (e.g. along the lines of Hochman–Meyerovitch).	t-dynamics new-contributor	746/0	Mathlib.lean,Mathlib/Dynamics/SymbolicDynamics/Basic.lean,Mathlib/Tactic/Translate/ToAdditive.lean	3	180	['Sfgangloff', 'botbaki-review', 'eric-wieser', 'github-actions', 'kckennylau', 'mathlib4-merge-conflict-bot', 'sgouezel']	sgouezel assignee:sgouezel	14-76291 14 days ago	15-75589 15 days ago	126-24538 126 days
35313	LexinonCraft author:LexinonCraft	feat: IMO 2025 Q4	This adds a solution for problem 4 from the International Math Olympiad 2025. ---	awaiting-author new-contributor IMO	631/0	Archive.lean,Archive/Imo/Imo2025Q4.lean	2	4	['LexinonCraft', 'github-actions', 'jsm28']	jsm28 assignee:jsm28	14-73769 14 days ago	14-73769 14 days ago	3-30421 3 days
35316	mkaratarakis author:mkaratarakis	feat: lemmas for the analytic part of the proof of the Gelfond–Schneider theorem (Part 4/5)	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR t-number-theory new-contributor	86/0	Mathlib/NumberTheory/Transcendental/AnalyticPart.lean	1	5	['SnirBroshi', 'github-actions', 'mathlib-dependent-issues']	nobody	14-69001 14 days ago	14-69002 14 days ago	3-32077 3 days
33276	NicolaBernini author:NicolaBernini	feat: Rename List.reverse_perm to List.reverse_perm_self and List.reverse_perm' to List.reverse_perm_iff	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict new-contributor t-data	17/15	Mathlib/Algebra/BigOperators/Group/List/Basic.lean,Mathlib/Data/Finset/Dedup.lean,Mathlib/Data/List/Basic.lean,Mathlib/Data/List/Defs.lean,Mathlib/Data/List/Perm/Lattice.lean,Mathlib/Data/List/Permutation.lean,Mathlib/Data/Multiset/Defs.lean,Mathlib/NumberTheory/Divisors.lean	8	5	['Ruben-VandeVelde', 'github-actions', 'mathlib-merge-conflicts']	kim-em assignee:kim-em	14-57513 14 days ago	14-57514 14 days ago	4-4467 4 days
34674	Citronhat author:Citronhat	feat(Algebra/Order/Ring): replace ENNReal lemmas with WithTop versions	* Add `WithTop` versions of basic multiplicative order lemmas. * Use the new `WithTop` lemmas to replace `ENNReal` proofs and address six TODOs. * Fix a typo in the `pos_of_ne_zero` alias name.	merge-conflict t-algebra new-contributor label:t-algebra$	46/15	Mathlib/Algebra/Order/Monoid/Canonical/Defs.lean,Mathlib/Algebra/Order/Ring/WithTop.lean,Mathlib/Data/ENNReal/Operations.lean	3	5	['Citronhat', 'Ruben-VandeVelde', 'github-actions', 'mathlib-merge-conflicts']	Ruben-VandeVelde assignee:Ruben-VandeVelde	14-37247 14 days ago	14-37248 14 days ago	17-1225 17 days
35472	rao107 author:rao107	feat(Probability): add `CharacteristicFunction` section to binomial distribution	Adds characteristic function, mgf, and cgf of the binomial distribution. Also adds Integrable lemmas for binomial. This commit based heavily off of the CharacteristicFunction section for the Gaussian distribution. This PR is an alteration of #34866 which would have added similar theorems and lemmas. However, this PR builds on top of the API that @YaelDillies wrote in #28248. To be forthcoming, I used Claude Code to help with the proofs of `complexMGF_id_binomialReal` and `integrable_exp_mul_binomialReal`. The proofs are structured how I would want them and I would vouch for them. Any comments or suggestions for improvements are very welcome, thanks! --- - [ ] depends on: #28248 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR t-measure-probability new-contributor	367/0	Mathlib.lean,Mathlib/MeasureTheory/Integral/Bochner/Set.lean,Mathlib/Probability/Distributions/Binomial.lean	3	3	['github-actions', 'mathlib-dependent-issues']	nobody	14-694 14 days ago	14-49691 14 days ago	0-1007 16 minutes
32891	felixpernegger author:felixpernegger	feat(Topology/EMetricSpace): Introduction of ```Weak(Pseudo)EMetricSpace```	This PR introduces Weak(Pseudo)EMetric spaces, some basic properties and the fact that the One-Point Compactification of a Weak(Pseudo)EMetricSpace again has a Weak(Pseudo)EMetricSpace structure. This is inspired by discussion at [this](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/EMetricSpace.20is.20broken/near/530540916) and based on #27756. In short, types like ```ENNReal``` and ```ENat``` have a very "metric-like" structure, but are not yet a ```WeakPseudoEMetricSpace``` (which is the weakest form of a metric-like structure in mathlib). Therefore, the class```WeakEMetricSpace``` could be used to make more definitions applicable to ```ENNReal```, for instance EVartiationOn ([this](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Topology/EMetricSpace/BoundedVariation.html#eVariationOn)). As of now, this PR is still missing important properties like products and induced (and therefore subtypes) of ```Weak(Pseudo)EMetricSpace```'s and instances ```ENNReal``` and ```ENat``` (which should be rather easy however with the one-point compactification property).	awaiting-author merge-conflict t-topology new-contributor	453/10	Mathlib.lean,Mathlib/Topology/EMetricSpace/Defs.lean,Mathlib/Topology/EMetricSpace/Weak.lean	3	30	['felixpernegger', 'github-actions', 'j-loreaux', 'mathlib4-merge-conflict-bot', 'plp127']	j-loreaux assignee:j-loreaux	13-29967 13 days ago	31-61701 1 month ago	12-62903 12 days
34954	brianrabern author:brianrabern	feat(Combinatorics/SimpleGraph/Acyclic): add colorable and chromaticN…	…umber bridges for acyclic and tree graphs Add thin bridge lemmas expressing that acyclic graphs (forests) and trees are 2-colorable, and that their chromatic number is at most 2, directly in terms of `Colorable` and `chromaticNumber`. The existing `IsAcyclic.isBipartite` already proves this via the definitional equality `IsBipartite = Colorable 2`, but these bridges improve discoverability for users who reason about `Colorable` or `chromaticNumber` without passing through `IsBipartite`. This is a first step toward building out the graph coloring API. New declarations: - `IsAcyclic.colorable_two` - `IsTree.colorable_two` - `IsAcyclic.chromaticNumber_le_two` - `IsTree.chromaticNumber_le_two` All are one-line proofs reusing existing results; no new imports needed. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-combinatorics new-contributor	16/0	Mathlib/Combinatorics/SimpleGraph/Acyclic.lean	1	1	['github-actions']	b-mehta assignee:b-mehta	12-74817 12 days ago	25-12288 25 days ago	25-12336 25 days
28246	Sebi-Kumar author:Sebi-Kumar	feat(AlgebraicTopology/FundamentalGroupoid): the n-sphere is simply connected for n > 1	Prove that the `n`-dimensional sphere (i.e., the unit sphere centered at the origin in `(n + 1)`-dimensional real Euclidean space) is a simply connected space for `n > 1`. This proof follows Hatcher's "Algebraic Topology"; we first prove a general lemma about decomposing loops and then exploit the fact that non-surjective loops in the sphere are homotopically trivial. Note: To get this file to build, I edited `Mathlib/Tactic/Linter/DirectoryDependency.lean` to remove the restrictions on AlgebraicTopology files importing Geometry, NumberTheory, and FieldTheory files. Thank you to those who shared their expertise [here](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Warning.20that.20AlgebraicTopology.20can't.20import.20SetTheory/with/533833638). As I understand it, this is just a short-term solution, so I would appreciate feedback on what to do about this situation. Note: I am unsure where exactly the file `SimplyConnectedSphere.lean` should go or whether that is an appropriate name for the file, so feedback there would be appreciated. --- To provide additional context, this code was written as a part of the Fields Undergraduate Summer Research Program at the University of Western Ontario under the supervision of Chris Kapulkin and Daniel Carranza. - [x] depends on: #28208 - [x] depends on: #28198 - [x] depends on: #28185 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author new-contributor t-algebraic-topology	343/3	Mathlib.lean,Mathlib/AlgebraicTopology/FundamentalGroupoid/SimplyConnectedSphere.lean,Mathlib/Tactic/Linter/DirectoryDependency.lean	3	17	['dagurtomas', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'robin-carlier']	robin-carlier assignee:robin-carlier	12-35033 12 days ago	12-35033 12 days ago	17-46260 17 days
35568	goliath-klein author:goliath-klein	refactor(PiTensorProduct/{InjectiveNorm, ProjectiveNorm}): switch NormedSpace instance to `projectiveSeminorm`	We switch the `NormedSpace` instance on `PiTensorProduct`s from `injectiveSeminorm` to `projectiveSeminorm` and update all follow-up results. The signature of `norm_eval_le_projectiveSeminorm` is changed to match the one of `norm_eval_le_injectiveSeminorm`. This is the second in a series of three PRs with the goal to [deprecate `PiTensorProuduct.injectiveSeminorm`](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/injectiveSeminorm/with/568798633). --- - [ ] depends on: #35567 Co-authored-by: Davood H. H. Tehrani [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR new-contributor	108/173	Mathlib/Analysis/Normed/Module/PiTensorProduct/InjectiveSeminorm.lean,Mathlib/Analysis/Normed/Module/PiTensorProduct/ProjectiveSeminorm.lean,Mathlib/LinearAlgebra/PiTensorProduct.lean	3	3	['github-actions', 'mathlib-dependent-issues']	nobody	12-26661 12 days ago	12-27155 12 days ago	0-1535 25 minutes
35421	farmanb author:farmanb	feat(CategoryTheory): preradicals in abelian categories	Following Stenström's development, define preradicals on an abelian category, together with the quotient and colon constructions, and characterize radical preradicals via vanishing on quotients. This provides infrastructure for torsion theories in abelian categories. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-category-theory new-contributor	463/0	Mathlib.lean,Mathlib/CategoryTheory/Preradical/Basic.lean,Mathlib/CategoryTheory/Preradical/CokernelConstruction.lean,Mathlib/CategoryTheory/Preradical/Colon.lean,Mathlib/CategoryTheory/Preradical/Radical.lean	5	11	['farmanb', 'github-actions', 'joelriou']	nobody	11-85558 11 days ago	14-14257 14 days ago	0-44909 12 hours
35451	samueloettl author:samueloettl	feat(MeasureTheory.Function): compMeasurePreserving_iterate	--- These are useful for dynamics/ergodic theory. Possibly some of these could be simp lemmas but I'm not confident enough to say that they are so I didn't mark them as such. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-measure-probability new-contributor	32/0	Mathlib/MeasureTheory/Function/AEEqFun.lean,Mathlib/MeasureTheory/Function/LpSpace/Basic.lean	2	2	['github-actions']	RemyDegenne assignee:RemyDegenne	11-74814 11 days ago	15-17902 15 days ago	15-17986 15 days
34054	YellPika author:YellPika	feat(Order/OmegaCompletePartialOrder): OmegaCompletePartialOrder instance for `Sigma` with basic `ωScottContinuous` lemmas	This PR adds an `OmegaCompletePartialOrder` instance for `Sigma` along with `ωScottContinuous` lemmas for basic operations (`mk`, `fst`, `snd`). Appropriate lemmas are marked with `@[fun_prop]` so that the `fun_prop` tactic can automatically deduce `ωScottContinuous` proofs for functions involving `Sigma`s. --- - [x] depends on: #33941 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-order new-contributor please-merge-master	172/0	Mathlib/Data/Sigma/Order.lean,Mathlib/Order/OmegaCompletePartialOrder.lean	2	28	['Vierkantor', 'YellPika', 'github-actions', 'grunweg', 'mathlib-dependent-issues', 'mathlib-merge-conflicts']	grunweg assignee:grunweg	11-69332 11 days ago	12-4829 12 days ago	16-83148 16 days
34966	Deep0Thinking author:Deep0Thinking	feat(MeasureTheory): add `continuousWithinAt_Ici/Iic_primitive_Ioi/Iio` and `continuousOn_Ici/Iic_primitive_Ioi/Iio/Ici/Iic`	This PR proves: - `continuousWithinAt_Ici/Iic_primitive_Ioi/Iio` - `continuousOn_Ici/Iic_primitive_Ioi/Iio/Ici/Iic` - `integral_Ioi_sub_Ioi`, `integral_Ioi_sub_Ioi'`, `integral_Iio_sub_Iio`, `integral_Iio_sub_Iio'` - `Ioi_diff_Ioc` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-measure-probability new-contributor	125/1	Mathlib/MeasureTheory/Integral/DominatedConvergence.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/Basic.lean,Mathlib/Order/Interval/Set/LinearOrder.lean	3	14	['CoolRmal', 'Deep0Thinking', 'github-actions']	RemyDegenne assignee:RemyDegenne	11-16869 11 days ago	11-68791 11 days ago	23-47364 23 days
35620	inaciovasquez2020 author:inaciovasquez2020	feat(Fintype): choose element from nonempty finite type	This PR adds a noncomputable choice function for finite types with nonzero cardinality. * `Fintype.chooseOfCardNeZero` provides a witness of `α` from `[Fintype α]` assuming `Fintype.card α ≠ 0`. * A regression test is included in `MathlibTest/Fintype/ChooseOfCardNeZero.lean`. The construction follows existing mathlib choice patterns and is explicitly marked `noncomputable`.	new-contributor t-data	21/0	Mathlib.lean,Mathlib/Data/Fintype/Choose.lean,MathlibTest/Fintype/ChooseOfCardNeZero.lean	3	4	['github-actions', 'plp127', 'vihdzp']	nobody	10-58169 10 days ago	10-75085 10 days ago	10-75132 10 days
34937	tannerduve author:tannerduve	feat(Computability): semilattice instance on Turing degrees	This PR equips `TuringDegree` with a `SemilatticeSup` structure by introducing the Turing join, proving usual least-upper-bound properties, and lifting these to degrees (quotients). In support of this, it extends the existing `RecursiveIn` API with some lemmas used in the degree theory. The main contribution is the `SemilatticeSup` instance on `TuringDegree`. We define the Turing join as follows ``` turingJoin (f g) : ℕ → ℕ -- notation: f ⊕ g ``` and prove it is a least upper bound: * `left_le_join`, `right_le_join` * `join_le` * monotonicity and congruence lemmas (`join_mono`, `join_congr`) We lift this to degrees in `TuringDegree.sup`, `TuringDegree.le_sup_left`, `TuringDegree.le_sup_right`, and `TuringDegree.sup_le` ``` instance : SemilatticeSup TuringDegree ``` New additions to `RecursiveIn.lean`: - `liftPrim`, `liftPrimrec`, `RecursiveIn'`, `ComputableIn`, `ComputableIn₂`: Encodes partial/total functions between `Primcodable` types as `ℕ →. ℕ`, analogous to `Partrec`/`Computable`. - `of_eq`, `of_eq_tot`, `of_primrec`, `some`, `none`, `mono`, `subst`: Standard closure properties for `RecursiveIn`. - `cond_const`, `cond_core_rfind`, `cond`, `ComputableIn.cond`: Shows `RecursiveIn` is closed under conditionals when the guard is absolutely computable - `Nat.Partrec.recursiveIn`, `Computable.computableIn`: Every partrec/computable function is recursive in any oracle set. Small addition to `Partrec` we add to `Mathlib.Computability.Partrec` a small helper def (`Partrec.kronecker` and related `rfind` lemmas) representing the function that returns 1 if its two (unpaired) arguments are equal, and 0 otherwise, which is used in the proof of `cond` ## TODO Some current `RecursiveIn` proofs such as `cond_core_rfind` still work directly with the inductive constructors and are thus very long. A follow up could add a combinator-style closure library by essentially relativizing all the results and lemmas in `Partrec`, and proofs could be golfed heavily as they are in `Partrec` ## Note: AI Usage [Aleph prover](https://logicalintelligence.com/aleph-coding-ai/) was allowed to prove an earlier version of `cond_core_rfind`, which included stating and proving the lemma `cond_const` but the proofs have since been iterated on manually Cursor was allowed to run git commands and edit docstrings/headers, and was used in setting up the module structure of the files	new-contributor t-computability large-import	644/63	Mathlib/Computability/Partrec.lean,Mathlib/Computability/RecursiveIn.lean,Mathlib/Computability/TuringDegree.lean	3	14	['eric-wieser', 'github-actions', 'plp127', 'tannerduve', 'vihdzp']	nobody	10-4427 10 days ago	15-7510 15 days ago	25-57381 25 days
35504	JoaBjo author:JoaBjo	feat(Probability/Distributions/Exponential): add MGF, moments, and memoryless property	feat(Probability/Distributions/Exponential): add MGF, moments, and memoryless property Add the main analytic results for the exponential distribution: - moment-generating function `mgf id (expMeasure r) t = r / (r - t)` for `t < r` - mean `∫ x, x ∂(expMeasure r) = r⁻¹` - variance `Var[id; expMeasure r] = r⁻¹ ^ 2` - `ℒp` membership for all `p` - tail probability `P(X > x) = exp (-(r * x))` - memoryless property `P(X > s + t \| X > s) = P(X > t)` The MGF is computed by reducing to the known improper integral `∫ exp(c * x)` on `Ioi`, and integrability is deduced by contradiction from the positive closed-form value. The mean and variance are computed via the Gamma function integral `∫₀^∞ x^(n-1) exp(-r x) dx = Γ(n) / rⁿ`. The memoryless property follows from the exponential identity `exp(-(r(s+t))) = exp(-rt) * exp(-rs)`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-measure-probability new-contributor	200/0	Mathlib/Probability/Distributions/Exponential.lean	1	6	['JoaBjo', 'Timeroot', 'github-actions']	kex-y assignee:kex-y	9-74817 9 days ago	14-9216 14 days ago	14-9270 14 days
33746	ster-oc author:ster-oc	feat(Algebra/Module/ZLattice): align `ZSpan.floor` to `Int.floor` API	This PR adds some of the existent lemmas about `Int.floor`, `Int.ceil` and `Int.fract` to the `ZSpan` namespace. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict t-algebra new-contributor label:t-algebra$	353/145	Mathlib/Algebra/Module/ZLattice/Basic.lean,Mathlib/Algebra/Order/Floor/Ring.lean,Mathlib/Topology/Algebra/Order/Floor.lean	3	8	['github-actions', 'joelriou', 'mathlib-merge-conflicts', 'ster-oc']	joelriou assignee:joelriou	9-54145 9 days ago	9-54145 9 days ago	30-23357 30 days
35011	whocares-abt author:whocares-abt	feat(Combinatorics/SimpleGraph/Copy): add degree of copy less than original	add two theorems relating degree of a graph and it's copy	t-combinatorics new-contributor	17/0	Mathlib/Combinatorics/SimpleGraph/Copy.lean	1	12	['SnirBroshi', 'github-actions', 'themathqueen', 'vihdzp']	nobody	9-49229 9 days ago	23-49405 23 days ago	23-49442 23 days
34830	parabamoghv author:parabamoghv	feat(CategoryTheory/Monoidal): add definition of categorical groups	This PR defines of categorical groups, also known as coherent 2-groups, in mathlib. Motivation: Categorical groups are well-studied structures in monoidal category theory, but are not currently available in mathlib. The definitions in this PR follow the existing design patterns used for Category, MonoidalCategory, and BraidedCategory. This PR focuses on setting up the core structure and notation. Basic lemmas and further developments will be provided in a subsequent PR. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	WIP t-category-theory new-contributor	163/0	Mathlib.lean,Mathlib/CategoryTheory/Monoidal/CategoricalGroups/Basic.lean	2	26	['dagurtomas', 'github-actions', 'parabamoghv', 'robin-carlier']	robin-carlier assignee:robin-carlier	9-13037 9 days ago	12-49147 12 days ago	5-13156 5 days
33688	Citronhat author:Citronhat	feat(PMF): add expectation lemmas for Poisson PMF	This PR adds some basic results about the Poisson distribution, its `PMF`, and its expectation. New lemmas: * `poissonPMF_apply` — an unfolding lemma for `poissonPMF`. * `poissonPMFReal_mul_eq_succ_mul` — the standard recursion identity for the Poisson mass function. * `poissonPMFReal_hasSum_nmul` — shows that `fun n ↦ poissonPMFReal r n * n` has sum `r`. * `poissonPMF_tsum_nmul` — the corresponding identity at the level of the `PMF`. * `poissonPMF_coe_tsum_nmul` — the same result after coercion to `ℝ`. Both `ℝ`-valued and `ℝ≥0∞`-valued formulations are included so that these results can be used conveniently in both Lebesgue and Bochner integration contexts.	awaiting-author t-measure-probability new-contributor	21/0	Mathlib/Probability/Distributions/Poisson.lean	1	10	['Citronhat', 'DavidLedvinka', 'github-actions', 'urkud']	urkud assignee:urkud	9-6881 9 days ago	9-6881 9 days ago	47-76968 47 days
31766	SuccessMoses author:SuccessMoses	feat(Topology/EMetricSpace): continuity of arc length	fixes half of #31751 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-topology new-contributor	396/0	Mathlib.lean,Mathlib/Topology/EMetricSpace/ArcLength.lean,Mathlib/Topology/EMetricSpace/BoundedVariation.lean	3	40	['SnirBroshi', 'SuccessMoses', 'alreadydone', 'github-actions', 'grunweg', 'j-loreaux', 'mathlib-merge-conflicts']	nobody	8-85842 8 days ago	8-85843 8 days ago	2-85434 2 days
33257	NickAdfor author:NickAdfor	feat(Combinatorics/SimpleGraph/Bipartite): Odd Cycle Theorem (A Solution to TODO)	Prove bipartite iff all cycles are even This PR formalizes the classical graph theory theorem: a graph is bipartite if and only if all its cycles have even length. Co-authored-by: Nick Adfor Co-authored-by: Yue Sun Co-authored-by: Aristotle AI --- ## Main results - `SimpleGraph.bipartite_iff_all_cycles_even` : the main equivalence theorem ## Key supporting lemmas - `SimpleGraph.even_length_iff_same_color` : parity lemma for 2-colorings - `SimpleGraph.even_length_iff_even_bypass_length` : bypass length parity - `SimpleGraph.even_cycle_length_of_path` : cycle construction lemma - `SimpleGraph.bypass_eq_nil_of_closed` : closed path properties ## Proof outline 1. For bipartite graphs: use the 2-coloring to show that in a 2-coloring, a walk has even length iff its endpoints have the same color. 2. For cycles (start = end), this forces even length. 3. For the converse: if all cycles are even, construct a 2-coloring using the `two_colorable_iff_forall_loop_even` characterization. 4. Show this coloring is valid using bypass operations and path properties. ## Technical notes - Uses `SimpleGraph.Walk` for path/cycle representation - Handles both `IsPath` and `IsCycle` predicates - Uses bypass operations (`takeUntil`, `dropUntil`, `bypass`) to analyze walks - Requires `DecidableEq V` for some lemmas - Uses classical logic for case analysis ## Reviewer notes - The proof uses induction on walks and case analysis on colorings - Some lemmas (like `even_length_iff_same_color`) could be extracted to more general locations - All theorems are in the `SimpleGraph` namespace - The `bipartite_iff_all_cycles_even` theorem provides the complete characterization	t-combinatorics new-contributor	164/8	Mathlib/Combinatorics/SimpleGraph/Bipartite.lean,Mathlib/Combinatorics/SimpleGraph/ConcreteColorings.lean	2	70	['IvanRenison', 'NickAdfor', 'Rida-Hamadani', 'SnirBroshi', 'github-actions', 'kmill', 'mitchell-horner', 'vihdzp', 'vlad902']	kmill assignee:kmill	8-74816 8 days ago	24-73750 24 days ago	33-6434 33 days
34599	cameronfreer author:cameronfreer	feat(Logic/Equiv/Fintype): generalize toCompl and exists_extending_pair to finite source	Generalize the Equiv subtype-extension API so it only needs finiteness of the source subtype, then use that to drastically simplify `Equiv.Perm.isMultiplyPretransitive`. ### Changes to `Logic/Equiv/Fintype.lean` * `Equiv.toCompl`: generalize from `[Finite α]` to `[Finite {x \| p x}]`. New proof (due to tb65536) uses finset symmetric differences to avoid needing finiteness of the ambient type. * `Equiv.extendSubtype` and related lemmas: adapt to `[Finite {x \| p x}]`. * `Equiv.Perm.exists_extending_pair`: strengthen from `[Finite β]` to `[Finite α]`. Given two injective functions `f, g : α → β` where `α` is finite, there exists `σ : Perm β` with `σ ∘ f = g`. The target `β` can now be infinite. ### Changes to `MultipleTransitivity.lean` * `Equiv.Perm.isMultiplyPretransitive`: replace ~70-line manual bijectivity construction with a two-line proof via `exists_smul_eq_embedding`. * `exists_smul_eq_embedding`: rewire to use `exists_extending_pair` directly (removing the old cardinal-arithmetic proof `exists_extending_pair_of_finite_source`). ### Application Used in formalizing de Finetti's theorem (exchangeability ⇒ contractability): https://github.com/cameronfreer/exchangeability/blob/03a854a2/Exchangeability/Contractability.lean#L459 Co-authored-by: tb65536	new-contributor t-group-theory	49/77	Mathlib/GroupTheory/GroupAction/MultipleTransitivity.lean,Mathlib/Logic/Equiv/Fintype.lean	2	24	['LLaurance', 'cameronfreer', 'github-actions', 'mathlib-merge-conflicts', 'tb65536']	mattrobball assignee:mattrobball	8-74815 8 days ago	8-81198 8 days ago	18-36266 18 days
34419	ster-oc author:ster-oc	feat(RCLike): add `Continuous.re` and similar	This PR adds dot notation for `re`, `im`, `conj` and `ofReal` for `Continuous`, `LipschitzWith` and `Memℓp`. Given `hf : Continuous f` it allows to use `hf.re` to express `Continuous (fun x ↦ (f x).re)`, similarly to the usual `hf.add hg`. I also can add the same features for `Summable` but I am not sure where to place them, suggestions are appreciated! --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-analysis new-contributor	186/41	Mathlib/Analysis/Normed/Group/Uniform.lean,Mathlib/Analysis/Normed/Lp/lpSpace.lean,Mathlib/Analysis/RCLike/Basic.lean	3	14	['github-actions', 'j-loreaux', 'ster-oc']	j-loreaux assignee:j-loreaux	8-11540 8 days ago	8-11540 8 days ago	8-31544 8 days
26479	thefundamentaltheor3m author:thefundamentaltheor3m	feat(Analysis/Complex/CauchyIntegral): Cauchy–Goursat for Unbounded Rectangles	In this PR, we prove versions of the Cauchy-Goursat theorem where the contours in question are rectangular and unbounded (ie, where the contours look like the $\bigsqcup$ symbol). I am not sure if I have formalised these in the best way, or if `Analysis.Complex.CauchyIntegral` is the best place for them (it might be prudent to reorganise the file into multiple files at some point), but I believe this is a useful result. Suggestions welcome. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-analysis new-contributor sphere-packing	205/0	Mathlib/Analysis/Complex/CauchyIntegral.lean	1	6	['github-actions', 'j-loreaux', 'loefflerd', 'mathlib4-merge-conflict-bot', 'thefundamentaltheor3m', 'wwylele']	urkud assignee:urkud	7-85962 7 days ago	7-85962 7 days ago	34-12694 34 days
35582	nielsvoss author:nielsvoss	feat(Analysis/InnerProductSpace): add theorems about the adjoint, kernel, range, and orthogonal complement	Add theorems about the interaction between the adjoint, kernel, range, and orthogonal complement from Linear Algebra Done Right 4th edition. This includes theorems from the singular value decomposition section which are needed for #33731. - `LinearMap.orthogonal_ker` and `LinearMap.orthogonal_range` are inherited from the `ContinuousLinearMap` versions. - `ker_adjoint_comp_self` and `adjoint_comp_self_injective_iff` are new theorems for both `ContinuousLinearMap` and finite-dimensional `LinearMap`. - `LinearMap.range_adjoint_comp_self` and `LinearMap.finrank_range_adjoint` apply to only finite-dimensional `LinearMap`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-analysis new-contributor	52/0	Mathlib/Analysis/InnerProductSpace/Adjoint.lean	1	7	['github-actions', 'j-loreaux', 'themathqueen']	j-loreaux assignee:j-loreaux	7-84977 7 days ago	7-84978 7 days ago	4-6953 4 days
34854	GrigorenkoPV author:GrigorenkoPV	chore(Combinatorics/Enumerative/Catalan): split into `Basic` & `Tree`	--- Split off from #34853 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	merge-conflict new-contributor	228/195	Mathlib.lean,Mathlib/Combinatorics/Enumerative/Catalan.lean,Mathlib/Combinatorics/Enumerative/Catalan/Basic.lean,Mathlib/Combinatorics/Enumerative/Catalan/Tree.lean,Mathlib/Combinatorics/Enumerative/DyckWord.lean,Mathlib/RingTheory/PowerSeries/Catalan.lean	6	5	['SnirBroshi', 'github-actions', 'mathlib-merge-conflicts', 'vihdzp']	thorimur assignee:thorimur	7-81800 7 days ago	7-81801 7 days ago	19-76299 19 days
35696	GrigorenkoPV author:GrigorenkoPV	fix(Data/Rel): change what `image_eq_cod_of_dom_subset` states	It used to be identical to its neighbor, `preimage_eq_dom_of_cod_subset`. Both lemmas seem to have been introduced in #25587. --- I think this is technically a breaking change? Not sure what has to be done here. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	new-contributor t-data	1/1	Mathlib/Data/Rel.lean	1	2	['github-actions', 'vihdzp']	nobody	7-77287 7 days ago	8-84846 8 days ago	8-84916 8 days
33985	YellPika author:YellPika	feat(Order/OmegaCompletePartialOrder): `OmegaCompletePartialOrder` instance for `Sum` with basic `ωScottContinuous` lemmas	This PR adds an `OmegaCompletePartialOrder` instance for `Sum`, along with `ωScottContinuous` lemmas for basic operations (`inl`, `inr`, `elim`). Appropriate lemmas are marked with `@[fun_prop]` so that the `fun_prop` tactic can automatically deduce `ωScottContinuous` proofs for functions involving `Sum`s (e.g. see the proof of `Sum.ωScottContinuous_map`). --- - [x] depends on: #33941 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-order new-contributor large-import	191/1	Mathlib/Data/Sum/Basic.lean,Mathlib/Data/Sum/Order.lean,Mathlib/Order/OmegaCompletePartialOrder.lean,Mathlib/Order/ScottContinuity.lean	4	20	['Vierkantor', 'YellPika', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'vihdzp']	bryangingechen assignee:bryangingechen	7-74796 7 days ago	19-16559 19 days ago	28-70415 28 days
35481	FrankieeW author:FrankieeW	chore(NumberTheory/Zsqrtd): inline duplicated order lemmas into instances	This PR follows reviewer feedback by removing duplicated order/additive wrapper theorems in `Zsqrtd` and inlining the proofs into the corresponding typeclass instances. Changes include: - remove redundant wrappers such as `Zsqrtd.le_total`, `Zsqrtd.add_le_add_left`, `Zsqrtd.le_of_add_le_add_left`, `Zsqrtd.add_lt_add_left`, and `Zsqrtd.le_antisymm` - keep the canonical API through `LinearOrder` / ordered additive structure fields - update downstream use in `PellMatiyasevic` to the canonical theorem (`_root_.le_antisymm`) This reduces namespace-level duplicate APIs and keeps proofs aligned with standard typeclass lemmas. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-number-theory new-contributor	26/10	Mathlib/NumberTheory/PellMatiyasevic.lean,Mathlib/NumberTheory/Zsqrtd/Basic.lean	2	8	['FrankieeW', 'github-actions', 'vihdzp']	MichaelStollBayreuth assignee:MichaelStollBayreuth	7-74788 7 days ago	12-69784 12 days ago	14-30197 14 days
35735	mkaratarakis author:mkaratarakis	feat(NumberTheory): analytical properties and lower bounds for Gelfond-Schneider auxiliary function	This PR is the third component in the formalization of the Gelfond-Schneider Theorem (Hilbert's Seventh Problem). It connects the algebraically constructed auxiliary function `R(x)` to its analytical properties, establishing the exact order of vanishing and the fundamental lower bound on the norm of its non-zero derivative evaluation. Following the argument in Loo-Keng Hua's Introduction to Number Theory (Chapter 17.9, equations (4) and (5)), we define the minimal non-vanishing derivative order $r$ and scale the evaluation to an algebraic integer to compute its norm. 1. (`iteratedkDeriv_R_eq_zero` & `order_geq_n`): We verify that the coefficient vector $\eta$ (chosen via Siegel's lemma in the previous PR) forces the first $n$ derivatives of the auxiliary function $R(x)$ to vanish at the points $x \in \{1, 2, \dots, m\}$. Consequently, the analytical order of $R(x)$ at these points is at least $n$. 2. We extract $r$, the exact minimal order of vanishing of $R(x)$ among all points $1 \le l \le m$, and prove that $n \le r$. 3. We define the non-zero algebraic number $\rho = (\log \alpha)^{-r} R^{(r)}(l_0)$. 4. We prove the crucial textbook step that scaling $\rho$ by $c_1^{r+2mq}$ (formalized here as `cρ`) results in an algebraic integer in $\mathcal{O}_K$. 5. Because $c_1^{r+2mq} \rho$ is a non-zero algebraic integer, the absolute value of its norm is at least $1$. We use this to formally prove the strict lower bound on the absolute norm of the unscaled $\rho$: $\|N(\rho)\| > c_1^{-h(r+2mq)} > c_5^{-r}$. --- - [ ] depends on: #35734 [optional extra text] [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR t-number-theory new-contributor	1141/0	Mathlib.lean,Mathlib/NumberTheory/Transcendental/GelfondSchneider/MainAlg.lean,Mathlib/NumberTheory/Transcendental/GelfondSchneider/MainAlgSetup.lean,Mathlib/NumberTheory/Transcendental/GelfondSchneider/MainOrder.lean	4	3	['github-actions', 'mathlib-dependent-issues']	nobody	7-69259 7 days ago	8-2835 8 days ago	0-2842 47 minutes
35280	khwilson author:khwilson	feat(Mathlib/Analysis/Polynomial/MahlerMeasure): Mahler Measure estimate in terms of supNorm	The Mahler measure of a polynomial is bounded above by `√(p.natDegree + 1) * p.supNorm`. This is a tighter estimate than `(p.natDegree + 1) * p.supNorm`, which is implied by `mahlerMeasure_le_sum_norm_coeff`. AI Usage: Claude Code (Opus 4.6) provided first drafts for several sorries in the main calc block. Gemini Pro was used for one-off looks ups of lemma names like `ae_restrict_iff'`. The final code was edited by me. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-analysis new-contributor	67/0	Mathlib/Analysis/Polynomial/MahlerMeasure.lean	1	12	['github-actions', 'j-loreaux', 'khwilson', 'mathlib-merge-conflicts']	j-loreaux assignee:j-loreaux	7-68212 7 days ago	7-68288 7 days ago	17-74482 17 days
29458	LiamSchilling author:LiamSchilling	feat(MvPolynomial/WeightedHomogenous): relate `weightedTotalDegree` to `degrees` and `degreeOf`	`weightedTotalDegree` is the most general notion of multivariate degree in mathlib. These theorems show that it specializes to `degrees` and `degreeOf` with specialized weights. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author new-contributor t-ring-theory	17/0	Mathlib/RingTheory/MvPolynomial/Homogeneous.lean	1	7	['LiamSchilling', 'chrisflav', 'github-actions']	chrisflav assignee:chrisflav	7-48212 7 days ago	162-41406 5 months ago	14-19311 14 days
35755	Vilin97 author:Vilin97	feat(Analysis/ODE): forward Euler method convergence	## Summary - Define the forward Euler method (`ODE.EulerMethod.step`, `point`, `slope`, `path`, `deriv`) in `Analysis/ODE/EulerMethod.lean`. - Prove the local truncation error bound `dist_deriv_le`: `dist(deriv(t), v(t, path(t))) ≤ h(L + KM)`. - Prove the global error bound `dist_path_le` via Gronwall's inequality. - Prove convergence `tendsto_path`: `path(v, h, t₀, y₀, t) → sol(t)` as `h → 0⁺`. ## Motivation The forward Euler method is the simplest numerical method for ODEs and a natural complement to the existing Gronwall inequality (`Mathlib.Analysis.ODE.Gronwall`) and Picard-Lindelöf theorem (`Mathlib.Analysis.ODE.PicardLindelof`). This formalization is based on the [forward_euler](https://github.com/Vilin97/forward_euler) project. Depends on #35753. --- The initial proof was produced by [Aristotle](https://aristotle.harmonic.fun). The code was then iteratively refined (factoring out lemmas, golfing, simplifying proofs) using Claude Code (Claude Opus 4.6).	WIP new-contributor	297/0	Mathlib.lean,Mathlib/Analysis/ODE/EulerMethod.lean,Mathlib/Topology/Algebra/Order/Floor.lean,Mathlib/Topology/Algebra/Order/PiecewiseLinear.lean	4	3	['github-actions']	nobody	7-46248 7 days ago	7-48459 7 days ago	0-741 12 minutes
35738	GrigorenkoPV author:GrigorenkoPV	perf: remove some `aesop`s and `grind`s	--- Based on top of #35696. Needs benchmarking. After that I can split it into several smaller portions, if needed. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author new-contributor	236/92	Mathlib/Data/Finset/Card.lean,Mathlib/Data/Rel.lean,Mathlib/Data/Set/Lattice/Image.lean,Mathlib/Data/Set/Prod.lean,Mathlib/Logic/Equiv/Prod.lean,Mathlib/Order/Interval/Finset/Basic.lean,Mathlib/Order/KrullDimension.lean,Mathlib/Order/SupIndep.lean	8	6	['github-actions', 'themathqueen', 'vihdzp']	nobody	7-38067 7 days ago	7-38067 7 days ago	0-45682 12 hours
33662	Pjotr5 author:Pjotr5	feat(Algebra/Order/BigOperators/Expect): add lemmas and strict variants	### Summary - Combine `le_expect_nonempty_of_subadditive` and `le_expect_of_subadditive` into a single lemma `le_expect_of_subadditive`. The extra assumptions `(hs : s.Nonempty)` and `(h_zero : m 0 = 0)` are unnecessary (since `m 0 = 0` follows from `h_div`). This requires a small downstream update to `Mathlib/Analysis/RCLike/Basic.lean` (`norm_expect_le`). - Add strict-inequality variants: `expect_lt_expect`, `expect_lt`, `lt_expect`. - Add existence lemmas: `exists_le_of_expect_le_expect`, `exists_le_of_le_expect`, `exists_le_of_expect_le`, and `exists_lt_of_expect_lt_expect`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-algebra new-contributor label:t-algebra$	46/16	Mathlib/Algebra/Order/BigOperators/Expect.lean,Mathlib/Analysis/RCLike/Basic.lean	2	1	['github-actions']	thorimur assignee:thorimur	7-26275 7 days ago	31-38933 1 month ago	57-45043 57 days
35287	arnoudvanderleer author:arnoudvanderleer	feat(AlgebraicTopology/SimplicialSet): define isomorphisms in simplicial sets, and the coherent isomorphism simplicial set	show that any edge in a simplicial set, that is the image of the forward edge of the coherent isomorphism under a simplicial set morphism, is an isomorphism. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author new-contributor infinity-cosmos t-algebraic-topology	339/3	Mathlib.lean,Mathlib/AlgebraicTopology/SimplicialSet/CoherentIso.lean,Mathlib/AlgebraicTopology/SimplicialSet/CompStruct.lean,Mathlib/AlgebraicTopology/SimplicialSet/StdSimplex.lean	4	61	['arnoudvanderleer', 'github-actions', 'joelriou', 'robin-carlier']	nobody	7-5976 7 days ago	8-43044 8 days ago	3-39759 3 days
35569	goliath-klein author:goliath-klein	refactor(PiTensorProduct/{InjectiveNorm, ProjectiveNorm}): deprecate `injectiveSeminorm`	This PR: * Deprecates `PiTensorProduct.injectiveSeminorm` and supporting lemmas. * Moves the theory of `liftEquiv` from InjectiveSeminorm.lean to ProjectiveSeminorm.lean. No changes are introduced, beyond adding deprecation notices, adapting docstrings, and moving material between files. The PR leaves InjectiveSeminorm.lean almost empty. A new implementation of `injectiveSeminorm`, one which reflects the common mathematical definition, is to be done. This is the third in a series of three PRs with the goal to [deprecate `PiTensorProuduct.injectiveSeminorm`](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/injectiveSeminorm/with/568798633). --- - [ ] depends on: #35567 - [ ] depends on: #35568 Deprecations: - injectiveSeminorm - dualSeminorms_bounded - injectiveSeminorm_apply - norm_eval_le_injectiveSeminorm - injectiveSeminorm_le_projectiveSeminorm - injectiveSeminorm_tprod_le Preliminary work toward a reimplementation is at #33969. Co-authored-by: Davood H. H. Tehrani [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	blocked-by-other-PR new-contributor	290/366	Mathlib/Analysis/Normed/Module/PiTensorProduct/InjectiveSeminorm.lean,Mathlib/Analysis/Normed/Module/PiTensorProduct/ProjectiveSeminorm.lean,Mathlib/LinearAlgebra/PiTensorProduct.lean	3	3	['github-actions', 'mathlib-dependent-issues']	nobody	12-26464 12 days ago	12-27157 12 days ago	0-1492 24 minutes
32881	foderm author:foderm	feat(AlgebraicTopology/SimplicialObject): define simplicial homotopy	This file defines the notion of a combinatorial simplicial homotopy between two morphisms of simplicial objects. A first step towards proving homotopy invariance of simplicial homotopy. See [Zulip](https://leanprover.zulipchat.com/#narrow/channel/335062-homology/topic/Homotopy.20invariance.20of.20singular.20homology/with/562221688). I left in most of my comments to make it easier to understand what indices I used, since I had to shift most of them by 1 to avoid proofs of neq 0 or similar things. I guess they can be removed once we know that the equations are the correct ones. Additionally I added some simp lemmas and an identity, I hope this is more or less how this is usually done. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author new-contributor t-algebraic-topology	567/0	Mathlib.lean,Mathlib/AlgebraicTopology/SimplicialObject/ChainHomotopy.lean,Mathlib/AlgebraicTopology/SimplicialObject/SimplicialHomotopy.lean,Mathlib/AlgebraicTopology/SingularHomology/HomotopyInvariance.lean	4	17	['foderm', 'github-actions', 'joelriou']	nobody	15-11628 15 days ago	80-2192 2 months ago	0-14006 3 hours
34551	IlPreteRosso author:IlPreteRosso	refactor(Data.Finset.Antidiagonal): rename defs to `setAntidiagonal` and deprecate old names in namespace Finset	Main file is [Prod.lean](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Algebra/Order/Antidiag/Prod.html). Adds `Finset.HasMulAntidiagonal`, the multiplicative counterpart to `HasAntidiagonal`, linked via `@[to_additive existing]`. Split PR (current changes): This PR renames the set-based antidiagonal definitions to have a `set` prefix, distinguishing them from the typeclass-based API in `Prod.lean`. Only definitions are renamed in this PR. Theorem/lemma renames will follow in a subsequent PR. [MulAntidiagonal.lean](https://github.com/leanprover-community/mathlib4/blob/master/Mathlib/Data/Finset/MulAntidiagonal.lean) - `mulAntidiagonal` → `setMulAntidiagonal` - `addAntidiagonal` → `setAddAntidiagonal` (via `@[to_additive]`) [SMulAntidiagonal.lean](https://github.com/leanprover-community/mathlib4/blob/master/Mathlib/Data/Finset/SMulAntidiagonal.lean) - `SMulAntidiagonal` → `setSMulAntidiagonal` - `VAddAntidiagonal` → `setVAddAntidiagonal` (via `@[to_additive]`) Propagates to: - `Mathlib/RingTheory/HahnSeries/Multiplication.lean` - `Mathlib/RingTheory/HahnSeries/Summable.lean` --- Added deprecation aliases for the renamed definitions. [Finset/MulAntidiagonal.lean](https://github.com/leanprover-community/mathlib4/blob/master/Mathlib/Data/Finset/MulAntidiagonal.lean) ``` @[to_additive (attr := deprecated setAddAntidiagonal (since := "2026-01-31")), deprecated setMulAntidiagonal (since := "2026-01-31")] alias mulAntidiagonal := setMulAntidiagonal ``` [Finset/SMulAntidiagonal.lean](https://github.com/leanprover-community/mathlib4/blob/master/Mathlib/Data/Finset/SMulAntidiagonal.lean) ``` @[to_additive (attr := deprecated setVAddAntidiagonal (since := "2026-01-31")), deprecated setSMulAntidiagonal (since := "2026-01-31")] alias smulAntidiagonal := setSMulAntidiagonal ``` Propagates: [PointwiseSMul.lean](https://github.com/leanprover-community/mathlib4/blob/master/Mathlib/Data/Finsupp/PointwiseSMul.lean) - updated to use Set.vaddAntidiagonal (the original Set name) --- Full changes to be made: For a monoid `M`, `mulAntidiagonal n` returns the finset of pairs `(i, j)` such that `i * j = n`. [MulAntidiagonal.lean](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Data/Finset/MulAntidiagonal.html) - `mulAntidiagonal` → `setMulAntidiagonal` - `addAntidiagonal` → `setAddAntidiagonal` (via `@[to_additive]`) - All related theorems renamed accordingly: - `mem_setMulAntidiagonal` - `setMulAntidiagonal_mono_left`/`setMulAntidiagonal_mono_right` - `swap_mem_setMulAntidiagonal` - `support_setMulAntidiagonal_subset_mul` - `isPWO_support_setMulAntidiagonal` - `setMulAntidiagonal_min_mul_min` [SMulAntidiagonal.lean](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Data/Finset/SMulAntidiagonal.html) - `setSMulAntidiagonal` (lowercase `set` prefix) - `setVAddAntidiagonal` (via `@[to_additive setVAddAntidiagonal ...]`) - All related theorems use lowercase `set` prefix: - `mem_setSMulAntidiagonal` / `mem_setVAddAntidiagonal` - `setSMulAntidiagonal_mono_left`/`setSMulAntidiagonal_mono_right` / `setVAddAntidiagonal_mono_left`/`setVAddAntidiagonal_mono_right` - `support_setSMulAntidiagonal_subset_smul` / `support_setVAddAntidiagonal_subset_vadd` - `isPWO_support_setSMulAntidiagonal` / `isPWO_support_setVAddAntidiagonal` - `setSMulAntidiagonal_min_smul_min` / `setVAddAntidiagonal_min_vadd_min` [Prod.lean](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Algebra/Order/Antidiag/Prod.html) - Added explicit `@[to_additive]` target names: - `@[to_additive antidiagonal_congr ...]` for `mulAntidiagonal_congr` - `@[to_additive (attr := ext) antidiagonal_subtype_ext ...]` for `mulAntidiagonal_subtype_ext` - `@[to_additive antidiagonal_congr' ...]` for `mulAntidiagonal_congr'` - `@[to_additive (attr := simps) sigmaAntidiagonalEquivProd ...]` for `sigmaMulAntidiagonalEquivProd` [Multiplication.lean](https://leanprover-community.github.io/mathlib4_docs/Mathlib/RingTheory/HahnSeries/Multiplication.html) - Updated all VAdd antidiagonal references to use lowercase `set` prefix: - `setVAddAntidiagonal` - `mem_setVAddAntidiagonal` - `setVAddAntidiagonal_mono_left`/`setVAddAntidiagonal_mono_right` - `isPWO_support_setVAddAntidiagonal` - `support_setVAddAntidiagonal_subset_vadd` - `setVAddAntidiagonal_min_vadd_min` - Updated all Add antidiagonal references: - `mem_setAddAntidiagonal` - `swap_mem_setAddAntidiagonal` [Summable.lean](https://leanprover-community.github.io/mathlib4_docs/Mathlib/RingTheory/HahnSeries/Summable.html) - `setVAddAntidiagonal` references updated - `mem_setAddAntidiagonal` references updated [PowerSeries.lean](https://leanprover-community.github.io/mathlib4_docs/Mathlib/RingTheory/HahnSeries/PowerSeries.html) - `mem_addAntidiagonal` → `mem_setAddAntidiagonal`	awaiting-author t-algebra new-contributor label:t-algebra$	67/47	Mathlib/Algebra/Order/Antidiag/Prod.lean,Mathlib/Data/Finset/MulAntidiagonal.lean,Mathlib/Data/Finset/SMulAntidiagonal.lean,Mathlib/Data/Set/MulAntidiagonal.lean,Mathlib/RingTheory/HahnSeries/Multiplication.lean,Mathlib/RingTheory/HahnSeries/Summable.lean	6	7	['IlPreteRosso', 'Ruben-VandeVelde', 'github-actions', 'jcommelin', 'kim-em', 'mathlib-merge-conflicts']	jcommelin assignee:jcommelin	14-51779 14 days ago	14-51779 14 days ago	20-8105 20 days
32555	ksenono author:ksenono	feat(Combinatorics/SimpleGraph/Matching): maximum and maximal matchings for Konig's theorem	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-combinatorics new-contributor	127/0	Mathlib/Combinatorics/SimpleGraph/DegreeSum.lean,Mathlib/Combinatorics/SimpleGraph/Matching.lean	2	24	['SnirBroshi', 'github-actions', 'jcommelin', 'ksenono']	awainverse assignee:awainverse	28-83315 1 month ago	28-83315 1 month ago	81-56016 81 days
27953	CoolRmal author:CoolRmal	feat(ProbabilityTheory): Conditional Jensen's Inequality	This PR adds conditional Jensen's inequality. I made some changes to Mathlib/Analysis/Convex/Approximation.lean because I need the sequence of affine functions to be bouneded above at each point. --- - [x] depends on: #31411 - [x] depends on: #31399 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-measure-probability new-contributor	137/20	Mathlib.lean,Mathlib/Analysis/Convex/Approximation.lean,Mathlib/MeasureTheory/Function/ConditionalExpectation/CondJensen.lean,Mathlib/MeasureTheory/MeasurableSpace/Constructions.lean	4	8	['CoolRmal', 'EtienneC30', 'github-actions', 'mathlib-dependent-issues', 'mathlib4-merge-conflict-bot']	sgouezel assignee:sgouezel	9-69946 9 days ago	16-23730 16 days ago	44-16245 44 days
31180	CoolRmal author:CoolRmal	feat(Analysis): a closed convex set is the intersection of countably many half-spaces in a separable Banach space	This lemma is needed in the proof of conditional Jensen's inequality: #27953 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author merge-conflict t-analysis new-contributor	70/13	Mathlib/Analysis/LocallyConvex/Separation.lean,Mathlib/Topology/Compactness/Lindelof.lean	2	44	['ADedecker', 'CoolRmal', 'EtienneC30', 'github-actions', 'j-loreaux', 'mathlib4-merge-conflict-bot']	nobody	42-3562 1 month ago	42-3563 1 month ago	3-22471 3 days

Stale delegated PRs

Number	Author	Title	Description	Labels	+/-	Modified files (first 100)	📝	💬	All users who commented or reviewed	Assignee(s)	Updated	Last status change	total time in review
14712	FR-vdash-bot author:FR-vdash-bot	perf: change instance priority and order about `OfNat`	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated merge-conflict t-algebra slow-typeclass-synthesis label:t-algebra$	49/20	Mathlib/Algebra/Group/Nat.lean,Mathlib/Algebra/Group/ZeroOne.lean,Mathlib/Algebra/Homology/Embedding/Basic.lean,Mathlib/Algebra/Tropical/Basic.lean,Mathlib/Data/BitVec.lean,Mathlib/Data/Nat/Cast/Defs.lean,Mathlib/Data/Rat/Defs.lean,Mathlib/Data/UInt.lean,Mathlib/NumberTheory/ArithmeticFunction.lean	9	24	['FR-vdash-bot', 'MichaelStollBayreuth', 'eric-wieser', 'github-actions', 'j-loreaux', 'leanprover-bot', 'mathlib-bors']	nobody	514-39986 1 year ago	516-63462 1 year ago	0-0 0 seconds
19275	eric-wieser author:eric-wieser	fix: if nolint files change, do a full rebuild	Otherwise CI will succeed when removing entries from the file, but fail later when someone changes something unrelated. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated merge-conflict	8/0	lakefile.lean	1	20	['YaelDillies', 'adomani', 'eric-wieser', 'github-actions', 'grunweg', 'mathlib-bors']	nobody	334-26330 11 months ago	334-26330 11 months ago	0-0 0 seconds
25473	adomani author:adomani	feat(CI): check that Mathlib files have lean or md extension	Twice recently there have been files with an "intended" `.lean` extension in `Mathlib/`: * #24942, ending in `;lean`; * #25457, ending in `.Lean`. `mk_all` does not add these files to `Mathlib.lean`, since they do not end in `.lean` and this later causes problems. This CI step checks that all files in `Mathlib/` end with `.lean` or `.md`. See #25474 for a test where the new step [correctly fails](https://github.com/leanprover-community/mathlib4/actions/runs/15464097783/job/43532018379?pr=25474). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated CI	10/0	.github/workflows/lint_and_suggest_pr.yml	1	10	['adomani', 'bryangingechen', 'github-actions', 'grunweg', 'mathlib-bors']	nobody	272-31979 8 months ago	272-32869 8 months ago	0-0 0 seconds
13483	adomani author:adomani	feat: automatically replace deprecations	This PR introduces `lake exe update_deprecations` that uses the cache to automatically replace deprecated declarations with the corresponding un-deprecated one. The script handles namespacing, replacing a possibly non-fully-qualified, deprecated name with the fully-qualified non-deprecated name. It is also possible to use ```bash lake exe update_deprecations --mods One.Two.Three,Dd.Ee.Ff ``` to limit the scope of the replacements to the modules `One.Two.Three` and `Dd.Ee.Ff`. This is intended to be a first step in automating updates: combining this with a linter that emits appropriate warnings, the functionality of `lake exe update_deprecations` can be extended to perform more complicated updates. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author delegated merge-conflict t-meta	306/0	Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/UpdateDeprecations.lean,MathlibTest/UpdateDeprecations.lean,lakefile.lean,scripts/README.md,scripts/update_deprecations.lean	7	16	['YaelDillies', 'adomani', 'github-actions', 'j-loreaux', 'jcommelin', 'leanprover-community-bot-assistant', 'mathlib-bors', 'sgouezel']	joneugster assignee:joneugster	266-73641 8 months ago	266-73642 8 months ago	0-0 0 seconds
17627	hrmacbeth author:hrmacbeth	feat: universal properties of vector bundle constructions	Characterizations for the smoothness of maps into the total spaces of (1) the direct sum of two vector bundles; (2) the pullback of a vector bundle. This gap in the library was exposed by #17358. --- - [x] depends on: #22804 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated merge-conflict t-differential-geometry	311/9	Mathlib/Data/Bundle.lean,Mathlib/Geometry/Manifold/VectorBundle/Basic.lean,Mathlib/Geometry/Manifold/VectorBundle/Pullback.lean,Mathlib/Topology/FiberBundle/Constructions.lean	4	24	['PatrickMassot', 'github-actions', 'grunweg', 'hrmacbeth', 'j-loreaux', 'leanprover-community-bot-assistant', 'mathlib-bors', 'mathlib4-dependent-issues-bot', 'sgouezel']	grunweg assignee:grunweg	242-64240 7 months ago	242-64240 7 months ago	0-0 0 seconds
26911	JovanGerb author:JovanGerb	chore: fix naming of `mono` and `monotone`	The naming convention says: "We use `_mono` for `a ≤ b → f a ≤ f b` and `_anti` for `a ≤ b → f b ≤ f a`, so we also use `_monotone` for `Monotone f`, `_antitone` for `Antitone f`, `_strictMono` for `StrictMono f`, `_strictAnti` for `StrictAnti f`, etc..." This PR swaps `mono`/`anti` and `monotone`/`antitone` where required so that `monotone` refers to `Monotone`, while `mono` refers to a lemma that might be tagged with `@[gcongr]` This PR does not address - `mul_left_monotone` and `mul_right_monotone` are exactly the wrong way around - `monotone_right`/`mono_right` vs `right_monotone`/`right_mono` - `monotone_arcsin` vs `arcsin_monotone` edit: TODO: `ideal_mono` and friends --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated merge-conflict	238/171	Archive/Imo/Imo1962Q1.lean,Archive/Wiedijk100Theorems/AbelRuffini.lean,Archive/Wiedijk100Theorems/SumOfPrimeReciprocalsDiverges.lean,Counterexamples/DiscreteTopologyNonDiscreteUniformity.lean,Mathlib/Algebra/Group/Pointwise/Finset/Basic.lean,Mathlib/Algebra/Group/Pointwise/Set/Basic.lean,Mathlib/Algebra/Order/Field/Basic.lean,Mathlib/Algebra/Order/Group/Basic.lean,Mathlib/Algebra/Order/Group/Finset.lean,Mathlib/Algebra/Order/Group/PosPart.lean,Mathlib/Algebra/Order/GroupWithZero/Unbundled/Basic.lean,Mathlib/Algebra/Order/Monoid/Unbundled/Basic.lean,Mathlib/Algebra/Order/Monoid/Unbundled/Pow.lean,Mathlib/Algebra/Order/ToIntervalMod.lean,Mathlib/Algebra/Polynomial/Degree/CardPowDegree.lean,Mathlib/AlgebraicGeometry/IdealSheaf/Basic.lean,Mathlib/Analysis/Analytic/Composition.lean,Mathlib/Analysis/Convex/Deriv.lean,Mathlib/Analysis/Normed/Order/UpperLower.lean,Mathlib/Analysis/PSeries.lean,Mathlib/Analysis/SpecialFunctions/Pow/Continuity.lean,Mathlib/Analysis/SpecialFunctions/Trigonometric/Basic.lean,Mathlib/Analysis/SpecificLimits/Basic.lean,Mathlib/Analysis/SpecificLimits/FloorPow.lean,Mathlib/Combinatorics/SetFamily/Kleitman.lean,Mathlib/Combinatorics/SimpleGraph/Girth.lean,Mathlib/Combinatorics/SimpleGraph/Regularity/Chunk.lean,Mathlib/Combinatorics/SimpleGraph/Regularity/Lemma.lean,Mathlib/Computability/Ackermann.lean,Mathlib/Data/ENNReal/Inv.lean,Mathlib/Data/ENNReal/Operations.lean,Mathlib/Data/Nat/Choose/Factorization.lean,Mathlib/Data/Real/Pi/Bounds.lean,Mathlib/LinearAlgebra/AffineSpace/AffineMap.lean,Mathlib/MeasureTheory/Constructions/BorelSpace/Basic.lean,Mathlib/MeasureTheory/Constructions/Polish/Basic.lean,Mathlib/MeasureTheory/MeasurableSpace/MeasurablyGenerated.lean,Mathlib/MeasureTheory/OuterMeasure/Operations.lean,Mathlib/NumberTheory/Bertrand.lean,Mathlib/NumberTheory/FermatPsp.lean,Mathlib/NumberTheory/Padics/Hensel.lean,Mathlib/Order/Concept.lean,Mathlib/Order/Filter/AtTopBot/Defs.lean,Mathlib/Order/Fin/Basic.lean,Mathlib/Order/Heyting/Basic.lean,Mathlib/Order/Heyting/Boundary.lean,Mathlib/Order/Heyting/Regular.lean,Mathlib/Order/Hom/Set.lean,Mathlib/Order/Interval/Set/Fin.lean,Mathlib/Order/KrullDimension.lean,Mathlib/Order/UpperLower/Closure.lean,Mathlib/Probability/StrongLaw.lean,Mathlib/RingTheory/DedekindDomain/Different.lean,Mathlib/RingTheory/DedekindDomain/Ideal.lean,Mathlib/RingTheory/FractionalIdeal/Basic.lean,Mathlib/RingTheory/FractionalIdeal/Operations.lean,Mathlib/Topology/EMetricSpace/Lipschitz.lean,Mathlib/Topology/MetricSpace/Antilipschitz.lean,Mathlib/Topology/MetricSpace/Holder.lean	59	8	['JovanGerb', 'bryangingechen', 'github-actions', 'leanprover-community-bot-assistant', 'linesthatinterlace', 'mathlib-bors']	bryangingechen assignee:bryangingechen	235-71955 7 months ago	236-14579 7 months ago	2-60107 2 days
29855	eric-wieser author:eric-wieser	chore(Data/Finset/Sort): lemmas about `0 : Fin _` and `Fin.last _`	We already had these for `⟨0, ⋯⟩` and `⟨k - 1, ⋯⟩`. Moves: - `Finset.orderEmbOfFin_zero` -> `Finset.orderEmbOfFin_mk_zero` - `Finset.orderEmbOfFin_last` -> `Finset.orderEmbOfFin_mk_last` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated easy t-order t-data	17/7	Mathlib/Combinatorics/Enumerative/Composition.lean,Mathlib/Data/Finset/Sort.lean	2	4	['eric-wieser', 'github-actions', 'mathlib-bors', 'ocfnash']	nobody	139-8083 4 months ago	160-40173 5 months ago	0-0 0 seconds
27180	ADedecker author:ADedecker	feat: quotient of a monoid with zero by a multiplicative congruence	--- My motivation is getting a more conceptual construction of [ValuativeRel.ValueGroupWithZero](https://leanprover-community.github.io/mathlib4_docs/Mathlib/RingTheory/Valuation/ValuativeRel.html#ValuativeRel.ValueGroupWithZero), but I think this is of independent interest. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated merge-conflict t-algebra label:t-algebra$	141/26	Mathlib.lean,Mathlib/Data/Quot.lean,Mathlib/Data/Setoid/Basic.lean,Mathlib/GroupTheory/Congruence/Defs.lean,Mathlib/GroupTheory/Congruence/GroupWithZero.lean	5	32	['ADedecker', 'eric-wieser', 'github-actions', 'mathlib-bors', 'mathlib4-merge-conflict-bot', 'ocfnash']	ocfnash assignee:ocfnash	124-29672 4 months ago	124-29673 4 months ago	28-12053 28 days
25765	JovanGerb author:JovanGerb	feat(gcongr): lemma for rewriting inside divisibility	TODO: add test to show that we can rewrite using `a ≡ b [ZMOD n]` inside `n ∣ 2 * a + 1`. edit: it's not yet entirely clear if this is the right thing to do. edit: This lemma should be written using iff (or =), so that we can use it specifically when rewriting with a symmetric relation. Supporting equality in `gcongr` is still work in progress. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated t-data	5/0	Mathlib/Data/Int/ModEq.lean	1	3	['fpvandoorn', 'github-actions', 'mathlib-bors']	nobody	110-39674 3 months ago	264-25954 8 months ago	1-19951 1 day
25500	eric-wieser author:eric-wieser	feat: delaborators for metadata	Being able to see these is very important when debugging tactic failures. Probably these could be upstreamed, but I don't think that's a reason not to merge them here first. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author delegated merge-conflict t-meta large-import	75/3	Mathlib/Util/Delaborators.lean,Mathlib/Util/PPOptions.lean,MathlibTest/delaborators.lean	3	19	['JovanGerb', 'Rob23oba', 'eric-wieser', 'github-actions', 'kmill', 'mathlib-bors', 'mathlib4-merge-conflict-bot', 'plp127']	nobody	60-73388 2 months ago	105-50486 3 months ago	0-0 0 seconds
33702	JovanGerb author:JovanGerb	doc(Algebra/Quotient): update `HasQuotient.Quotient` doc-string	`HasQuotient.quotient'` has been deprecated (in #33037), so it should not be mentioned in the doc-string of `HasQuotent.Quotient`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated t-algebra label:t-algebra$	1/6	Mathlib/Algebra/Quotient.lean	1	4	['JovanGerb', 'github-actions', 'grunweg', 'mathlib-bors']	nobody	56-40060 1 month ago	56-48462 1 month ago	0-3706 1 hour
32401	ADedecker author:ADedecker	feat: monotonicity of D^n(U) in n and in U as CLMs	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated merge-conflict t-analysis	170/3	Mathlib/Analysis/Distribution/ContDiffMapSupportedIn.lean,Mathlib/Analysis/Distribution/TestFunction.lean	2	n/a	['ADedecker', 'faenuccio', 'github-actions', 'j-loreaux', 'mathlib-bors', 'mathlib4-merge-conflict-bot']	nobody	53-83146 1 month ago	unknown	unknown
31092	FlAmmmmING author:FlAmmmmING	feat(Algebra/Group/ForwardDiff.lean): Add theorem `sum_shift_eq_fwdDiff_iter`.	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated t-algebra new-contributor label:t-algebra$	17/1	Mathlib/Algebra/Group/ForwardDiff.lean	1	20	['BeibeiX0', 'FlAmmmmING', 'Ruben-VandeVelde', 'dagurtomas', 'github-actions', 'jcommelin', 'mathlib-bors', 'mathlib4-merge-conflict-bot']	dagurtomas assignee:dagurtomas	41-24750 1 month ago	41-24750 1 month ago	54-22055 54 days
33052	JovanGerb author:JovanGerb	feat: replace `rw??` tactic with `#infoview_search` command	This PR introduces the `#infoview_search` command. It gives an improved way of interacting with the library search from `rw??`, and hence this PR also deprecates `rw??` (`rw??` still works, but it displays a warning message suggesting to use `#infoview_search` instead). The difference is that `#infoview_search` is a command, so you type it once, and then you can use rewrite search in any tactic state in any place. This is more convenient than having to write out `rw??` every time. I have many improvements planned for `#infoview_search`, but this PR simply gives it the same capabilities that `rw??` currently has. One of those improvements is to also do `apply` search, and `apply at` search. That is why the name doesn't contain `rw` anymore. To prepare for more code developments around `#infoview_search`, I've moved the relevant files into a new folder `Mathlib.Tactic.InfoviewSearch`. Note that one annoyance with writing `#infoview_search` is that there is a linter warning. Should I remove the `#` from the command, or are we happy with this? ``` `#`-commands, such as '#infoview_search', are not allowed in 'Mathlib' Note: This linter can be disabled with `set_option linter.hashCommand false` ``` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated merge-conflict t-meta large-import file-removed	100/59	Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/Common.lean,Mathlib/Tactic/InfoviewSearch/InteractiveUnfold.lean,Mathlib/Tactic/InfoviewSearch/LibraryRewrite.lean,MathlibTest/LibraryRewrite.lean	6	6	['JovanGerb', 'fpvandoorn', 'github-actions', 'mathlib-bors', 'mathlib4-merge-conflict-bot']	adamtopaz assignee:adamtopaz	38-45408 1 month ago	38-45409 1 month ago	32-60516 32 days
34895	eric-wieser author:eric-wieser	chore: backquote tactic names in error messages	This matches the messages produced by `Lean.Meta.throwTacticEx`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated t-meta	15/15	Mathlib/Tactic/Abel.lean,Mathlib/Tactic/FieldSimp.lean,Mathlib/Tactic/Push.lean,Mathlib/Tactic/Ring/RingNF.lean,Mathlib/Util/AtLocation.lean,MathlibTest/abel.lean	6	2	['github-actions', 'grunweg', 'mathlib-bors']	nobody	26-35605 26 days ago	26-35605 26 days ago	0-0 0 seconds
27702	FLDutchmann author:FLDutchmann	feat(NumberTheory/SelbergSieve): define Lambda-squared sieves and prove important properties	This PR continues the work from #22052. Original PR: https://github.com/leanprover-community/mathlib4/pull/22052 - [x] depends on: #27820	delegated merge-conflict t-number-theory	186/7	Mathlib/NumberTheory/SelbergSieve.lean	1	44	['FLDutchmann', 'MichaelStollBayreuth', 'bryangingechen', 'github-actions', 'jcommelin', 'mathlib-bors', 'mathlib-merge-conflicts', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	MichaelStollBayreuth assignee:MichaelStollBayreuth	21-54781 21 days ago	21-54782 21 days ago	15-83343 15 days
31607	grunweg author:grunweg	chore: rename `continuous{,On,At,Within}_const` to `ContinuousFoo.const`	Zulip discussion: [#mathlib4 > Naming convention @ 💬](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Naming.20convention/near/447491526) --- - [x] depends on: #34441 - [x] depends on: #34688 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated merge-conflict awaiting-CI	357/369	Archive/Hairer.lean,Mathlib/Analysis/Analytic/Basic.lean,Mathlib/Analysis/Analytic/Inverse.lean,Mathlib/Analysis/Asymptotics/Lemmas.lean,Mathlib/Analysis/BoxIntegral/Box/Basic.lean,Mathlib/Analysis/BoxIntegral/UnitPartition.lean,Mathlib/Analysis/CStarAlgebra/ContinuousFunctionalCalculus/Continuity.lean,Mathlib/Analysis/CStarAlgebra/ContinuousFunctionalCalculus/Unital.lean,Mathlib/Analysis/Calculus/BumpFunction/FiniteDimension.lean,Mathlib/Analysis/Calculus/BumpFunction/InnerProduct.lean,Mathlib/Analysis/Calculus/DSlope.lean,Mathlib/Analysis/Calculus/Deriv/MeanValue.lean,Mathlib/Analysis/Calculus/DiffContOnCl.lean,Mathlib/Analysis/Calculus/FDeriv/Analytic.lean,Mathlib/Analysis/Calculus/FDeriv/Symmetric.lean,Mathlib/Analysis/Calculus/MeanValue.lean,Mathlib/Analysis/Calculus/Rademacher.lean,Mathlib/Analysis/Calculus/Taylor.lean,Mathlib/Analysis/Complex/AbelLimit.lean,Mathlib/Analysis/Complex/AbsMax.lean,Mathlib/Analysis/Complex/Basic.lean,Mathlib/Analysis/Complex/CauchyIntegral.lean,Mathlib/Analysis/Complex/HalfPlane.lean,Mathlib/Analysis/Complex/LocallyUniformLimit.lean,Mathlib/Analysis/Complex/PhragmenLindelof.lean,Mathlib/Analysis/Complex/RemovableSingularity.lean,Mathlib/Analysis/Complex/UpperHalfPlane/Basic.lean,Mathlib/Analysis/Complex/UpperHalfPlane/Metric.lean,Mathlib/Analysis/Complex/UpperHalfPlane/Topology.lean,Mathlib/Analysis/Convex/Cone/InnerDual.lean,Mathlib/Analysis/Convex/Exposed.lean,Mathlib/Analysis/Convex/Gauge.lean,Mathlib/Analysis/Convex/PartitionOfUnity.lean,Mathlib/Analysis/Convex/PathConnected.lean,Mathlib/Analysis/Convex/Side.lean,Mathlib/Analysis/Convex/StdSimplex.lean,Mathlib/Analysis/Convolution.lean,Mathlib/Analysis/InnerProductSpace/LinearPMap.lean,Mathlib/Analysis/InnerProductSpace/MeanErgodic.lean,Mathlib/Analysis/InnerProductSpace/OfNorm.lean,Mathlib/Analysis/InnerProductSpace/Projection/Submodule.lean,Mathlib/Analysis/Meromorphic/Order.lean,Mathlib/Analysis/Meromorphic/TrailingCoefficient.lean,Mathlib/Analysis/Normed/Affine/AddTorsor.lean,Mathlib/Analysis/Normed/Group/Continuity.lean,Mathlib/Analysis/Normed/Group/Lemmas.lean,Mathlib/Analysis/Normed/Module/Ball/Homeomorph.lean,Mathlib/Analysis/Normed/Module/Connected.lean,Mathlib/Analysis/Normed/Module/FiniteDimension.lean,Mathlib/Analysis/Normed/Module/Multilinear/Basic.lean,Mathlib/Analysis/Normed/Operator/Completeness.lean,Mathlib/Analysis/ODE/Gronwall.lean,Mathlib/Analysis/ODE/PicardLindelof.lean,Mathlib/Analysis/Seminorm.lean,Mathlib/Analysis/SpecialFunctions/Complex/Arg.lean,Mathlib/Analysis/SpecialFunctions/ContinuousFunctionalCalculus/Rpow/Isometric.lean,Mathlib/Analysis/SpecialFunctions/Elliptic/Weierstrass.lean,Mathlib/Analysis/SpecialFunctions/Gamma/Basic.lean,Mathlib/Analysis/SpecialFunctions/Gamma/Deligne.lean,Mathlib/Analysis/SpecialFunctions/Gaussian/GaussianIntegral.lean,Mathlib/Analysis/SpecialFunctions/Gaussian/PoissonSummation.lean,Mathlib/Analysis/SpecialFunctions/Integrability/Basic.lean,Mathlib/Analysis/SpecialFunctions/Integrals/Basic.lean,Mathlib/Analysis/SpecialFunctions/MulExpNegMulSq.lean,Mathlib/Analysis/SpecialFunctions/PolarCoord.lean,Mathlib/Analysis/SpecialFunctions/Pow/Continuity.lean,Mathlib/Analysis/SpecialFunctions/Pow/Deriv.lean,Mathlib/Analysis/SpecialFunctions/Trigonometric/Basic.lean,Mathlib/Analysis/SpecialFunctions/Trigonometric/Inverse.lean,Mathlib/Computability/AkraBazzi/SumTransform.lean,Mathlib/Dynamics/OmegaLimit.lean,Mathlib/Geometry/Euclidean/Angle/Oriented/Basic.lean,Mathlib/Geometry/Manifold/Bordism.lean,Mathlib/Geometry/Manifold/Complex.lean,Mathlib/Geometry/Manifold/Instances/Icc.lean,Mathlib/Geometry/Manifold/Instances/Real.lean,Mathlib/Geometry/Manifold/SmoothApprox.lean,Mathlib/MeasureTheory/Function/SpecialFunctions/Basic.lean,Mathlib/MeasureTheory/Integral/Bochner/Basic.lean,Mathlib/MeasureTheory/Integral/CircleIntegral.lean,Mathlib/MeasureTheory/Integral/CircleTransform.lean,Mathlib/MeasureTheory/Integral/DominatedConvergence.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/Basic.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/FundThmCalculus.lean,Mathlib/MeasureTheory/Integral/RieszMarkovKakutani/Real.lean,Mathlib/MeasureTheory/Measure/LevyProkhorovMetric.lean,Mathlib/MeasureTheory/Measure/Stieltjes.lean,Mathlib/NumberTheory/Cyclotomic/CyclotomicCharacter.lean,Mathlib/NumberTheory/Harmonic/ZetaAsymp.lean,Mathlib/NumberTheory/LSeries/AbstractFuncEq.lean,Mathlib/NumberTheory/LSeries/Deriv.lean,Mathlib/NumberTheory/LSeries/Dirichlet.lean,Mathlib/NumberTheory/LSeries/DirichletContinuation.lean,Mathlib/NumberTheory/LSeries/HurwitzZetaOdd.lean,Mathlib/NumberTheory/LSeries/PrimesInAP.lean,Mathlib/NumberTheory/Modular.lean,Mathlib/NumberTheory/ModularForms/Bounds.lean,Mathlib/NumberTheory/ModularForms/JacobiTheta/TwoVariable.lean,Mathlib/NumberTheory/NumberField/CanonicalEmbedding/NormLeOne.lean,Mathlib/NumberTheory/Padics/PadicIntegers.lean	181	10	['github-actions', 'j-loreaux', 'mathlib-bors', 'mathlib-merge-conflicts', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	15-55874 15 days ago	15-55874 15 days ago	0-1 1 second
34025	lua-vr author:lua-vr	feat(Integral.Bochner.Set): add `tendsto_setIntegral_of_monotone₀`	Adds the lemma `tendsto_setIntegral_of_monotone₀`, a version of `tendsto_setIntegral_of_monotone` requiring only `AEMeasurableSet` in the hypotheses. The previous version is redefined as a specialization. Also renames `integral_union_ae` to `setIntegral_union₀` for consistency with the rest of the library (it matches the existing `setIntegral_union`). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) Re-opened from #33206 and now taking respect for Windows users (thanks @ADedecker :).	delegated t-measure-probability	27/13	Mathlib/MeasureTheory/Integral/Bochner/Set.lean	1	5	['github-actions', 'mathlib-bors', 'ocfnash']	kex-y assignee:kex-y	15-21671 15 days ago	15-21671 15 days ago	32-48473 32 days
24965	erdOne author:erdOne	refactor: Make `IsLocalHom` take unbundled map	Under the current definition, `IsLocalHom f` and `IsLocalHom f.toMonoidHom` are not defeq, which causes quite some annoyances. We also have a consensus to not use `*HomClass` in definitions. As a result, we change `IsLocalHom` to take an unbundled function instead of a funlike. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated merge-conflict t-algebra label:t-algebra$	18/9	Mathlib/Algebra/Group/Units/Hom.lean,Mathlib/AlgebraicGeometry/Scheme.lean,Mathlib/Geometry/RingedSpace/LocallyRingedSpace.lean,Mathlib/Geometry/RingedSpace/OpenImmersion.lean,Mathlib/RingTheory/LocalRing/ResidueField/Basic.lean	5	15	['adomani', 'alreadydone', 'erdOne', 'eric-wieser', 'github-actions', 'jcommelin', 'leanprover-community-bot-assistant', 'mathlib-bors', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot', 'vihdzp']	mattrobball assignee:mattrobball	14-79872 14 days ago	14-79873 14 days ago	0-0 0 seconds
34249	xyzw12345 author:xyzw12345	feat(GroupTheory/GroupAction/Hom): connect existing definitions `MulDistribMulActionHom` and `DistribMulActionHom` using `to_additive`	In this PR, we defined `MulDistribMulActionHom` corresponding to `DistribMulActionHom`, which will be used in the multiplicative version of non-Abelian group cohomology. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated t-algebra label:t-algebra$	174/69	Mathlib/Algebra/GroupWithZero/Action/Defs.lean,Mathlib/GroupTheory/GroupAction/Hom.lean	2	7	['github-actions', 'mathlib-bors', 'ocfnash']	ocfnash assignee:ocfnash	12-17573 12 days ago	12-17593 12 days ago	29-31452 29 days
22366	kim-em author:kim-em	feat: `check_equalities` tactic for diagnosing defeq problems	The `check_equalities` tactic, which checks the typing of equalities in the goal, reporting discrepancies between the implicit type argument of the equality, and the inferred types of the left and right hand sides, at "instances and reducible" transparency. Reports from this tactic do not necessarily indicate a problem, although typically `simp` should reduce rather than increase the reported discrepancies. `check_equalities` may be useful in diagnosing uses of `erw`.	delegated t-meta	123/4	Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/Basic.lean,Mathlib/Tactic/CategoryTheory/CheckCompositions.lean,Mathlib/Tactic/CheckEqualities.lean,Mathlib/Tactic/Common.lean,MathlibTest/check_equalities.lean	7	19	['adomani', 'b-mehta', 'eric-wieser', 'github-actions', 'grunweg', 'kim-em', 'mathlib-bors', 'mathlib4-merge-conflict-bot']	nobody	9-79922 9 days ago	20-55952 20 days ago	0-0 0 seconds
33691	kim-em author:kim-em	feat(scripts): add find-ci-errors.sh to diagnose widespread CI failures	This PR adds a script that searches through recent failed CI workflow runs to find open PRs whose current CI contains a specific error string. Useful for diagnosing widespread CI issues affecting multiple PRs (e.g., infrastructure problems, toolchain bugs). Usage: ```bash # Find all PRs currently failing with a specific error ./scripts/find-ci-errors.sh "Error parsing args: cannot parse arguments" # Find PRs and automatically add please-merge-master label to trigger rebuilds ./scripts/find-ci-errors.sh --please-merge-master "cannot parse arguments" ``` The `--please-merge-master` flag skips PRs with merge conflicts, and the label is automatically removed by CI once the build completes. 🤖 Prepared with Claude Code	delegated merge-conflict CI	196/0	scripts/README.md,scripts/find-ci-errors.sh	2	6	['bryangingechen', 'github-actions', 'mathlib-bors', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot']	nobody	8-56210 8 days ago	8-56210 8 days ago	0-7055 1 hour
34734	FLDutchmann author:FLDutchmann	refactor(Tactic): change `ring` to allow for coefficients in a variable type	Add a parameter to the `ring` normal form that allows for the coefficients to be represented by a custom `BaseType`. `ring` (roughly) sets `BaseType` to be `Rat` and implements addition/multiplication/etc. using `norm_num`. The changes should not be noticeable to users. Care was taken to change as little of the implementation details as possible. This refactor is made in preparation of the `algebra` tactic proposed in #31508. In particular `algebra` will (roughly) set `BaseType` to `Ring.ExSum`. This will allow `algebra` to share much of its internals with `ring`. --- - [x] depends on: #34837 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated merge-conflict t-meta	1106/658	Mathlib/Tactic/Ring/Basic.lean,Mathlib/Tactic/Ring/Common.lean,Mathlib/Tactic/Ring/Compare.lean,Mathlib/Tactic/Ring/RingNF.lean,MathlibTest/ring.lean,scripts/noshake.json	6	60	['FLDutchmann', 'Vierkantor', 'eric-wieser', 'github-actions', 'leanprover-radar', 'mathlib-bors', 'mathlib-dependent-issues', 'mathlib-merge-conflicts']	Vierkantor assignee:Vierkantor	7-81806 7 days ago	7-81807 7 days ago	4-58524 4 days
33479	zcyemi author:zcyemi	feat(Geometry/Euclidean/Sphere/Power): Add theorem about cospherical points on two intersecting lines	--- Add `cospherical_of_mul_dist_eq_mul_dist_of_angle_eq_pi`. ~~This theorem is the converse of `EuclideanGeometry.mul_dist_eq_mul_dist_of_cospherical_of_angle_eq_pi`. However, the ambient type is required to be two-dimensional, i.e. `Fact (finrank ℝ V = 2)`. I don‘t think (not entirely sure) that lifting the ambient space from dimension 2 to arbitrary dimension is reasonable for this theorem, since the proof is entirely carried out in a two-dimensional plane. Therefore, I place this theorem in `Euclidean/Angle/Sphere` rather than `Euclidean/Sphere/Power`.~~ Deps: - [ ] depends on: #33365	delegated t-euclidean-geometry large-import	109/4	Mathlib/Geometry/Euclidean/Sphere/Basic.lean,Mathlib/Geometry/Euclidean/Sphere/Power.lean	2	18	['github-actions', 'jsm28', 'mathlib-bors', 'mathlib4-dependent-issues-bot', 'ocfnash', 'zcyemi']	JovanGerb assignee:JovanGerb	6-29247 6 days ago	6-29247 6 days ago	8-71084 8 days
35436	daniel-carranza author:daniel-carranza	feat(CategoryTheory/Monoidal/Closed): Prove the isomorphism of internal hom objects C(x \otimes y, z) and C(y, C(x, z))	Prove the currying-uncurrying isomorphism `C(x \otimes y, z) \iso C(y, C(x, z))` between internal hom objects of a closed monoidal category `C`. --- This result is connected to the infinity-cosmos project, and is used to prove that a closed monoidal category enriched in itself admits all cotensors. ~Line 81 currently contains a one-line proof in tactics mode `exact rfl`. When trying to use `rfl` outside of tactics mode, an error is thrown~ (Fixed, thank you @robin-carlier!). Any help with this (or any other aspect of the formalization) is greatly appreciated! [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated t-category-theory new-contributor infinity-cosmos	89/0	Mathlib.lean,Mathlib/CategoryTheory/Monoidal/Closed/InternalCurrying.lean	2	13	['dagurtomas', 'daniel-carranza', 'github-actions', 'joelriou', 'mathlib-bors', 'riccardobrasca', 'robin-carlier']	adamtopaz assignee:adamtopaz	5-84836 5 days ago	5-84836 5 days ago	8-435 8 days
34932	erdOne author:erdOne	feat(AlgebraicGeometry): formally etale morphisms	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated merge-conflict t-algebraic-geometry	163/12	Mathlib.lean,Mathlib/AlgebraicGeometry/Morphisms/Etale.lean,Mathlib/AlgebraicGeometry/Morphisms/FormallyEtale.lean,Mathlib/AlgebraicGeometry/Morphisms/RingHomProperties.lean,Mathlib/RingTheory/RingHom/Etale.lean	5	17	['chrisflav', 'erdOne', 'github-actions', 'joneugster', 'mathlib-bors', 'mathlib-merge-conflicts', 'ocfnash']	nobody	5-73308 5 days ago	6-40070 6 days ago	2-36163 2 days
30758	Timeroot author:Timeroot	chore: tag abs_inv and abs_div with grind=	--- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-algebra label:t-algebra$	2/1	Mathlib/Algebra/Order/Field/Basic.lean	1	n/a	['github-actions']	nobody	134-4686 4 months ago	unknown	unknown
35446	kbuzzard author:kbuzzard	perf: try lowering prio for A(0) instances, A a graded object	If Lean is looking for `Mul X` where `X` is coincidentally of the form `A 0` then the first thing it tries is `GradedMonoid.GradeZero.mul` which, if wrong, can take a long time to fail. In this PR I steer typeclass inference away from "A(0)-instances" by lowering their priority. Benchmarking is 100% green indicating that this decision is not hurting us. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) See [#mathlib4 > Typeclass Synthesis Regression @ 💬](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Typeclass.20Synthesis.20Regression/near/564417997) I initiated a new discussion about this PR here [#mathlib4 > priority hacks @ 💬](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/priority.20hacks/near/574353616)	delegated t-algebra label:t-algebra$	14/13	Mathlib/Algebra/DirectSum/Ring.lean,Mathlib/Algebra/GradedMonoid.lean	2	11	['Vierkantor', 'eric-wieser', 'github-actions', 'kbuzzard', 'leanprover-radar', 'mathlib-bors']	jcommelin assignee:jcommelin	5-41762 5 days ago	5-41762 5 days ago	7-51074 7 days
25737	robin-carlier author:robin-carlier	feat(AlgebraicTopology/SimplexCategory/GeneratorsRelations/NormalForms): Normal forms for `P_δ`s	We prove that admissible lists indeed provide a normal form for morphisms of satisfying `P_δ`. To this end, we introduce `standardδ`, a construction that takes a list and turn it into a composition of `δ i`s in `SimplexCategoryGenRel`. We then prove that, thanks to the first simplicial identity, composition on the left corresponds to simplicial insertion in the list. This gives existence of a normal form for every morphism satisfying `P_δ`. For unicity, we introduce an auxiliary function `simplicialEvalδ : (List ℕ) → ℕ → ℕ` and show that for admissible lists, it lifts to `ℕ` the `orderHom` attached to `toSimplexCategory.map standardδ`, and that we can recover elements of the list only by looking at values of this function. Part of a series of PR formalising that `SimplexCategoryGenRel` is equivalent to `SimplexCategory`. --- - [x] depends on: #25736 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) --- This PR continues the work from #21746. Original PR: https://github.com/leanprover-community/mathlib4/pull/21746	delegated t-category-theory t-algebraic-topology	182/2	Mathlib/AlgebraicTopology/SimplexCategory/GeneratorsRelations/NormalForms.lean	1	6	['github-actions', 'joelriou', 'mathlib-bors', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot']	nobody	134-27753 4 months ago	135-19469 4 months ago	0-22513 6 hours
29909	Vierkantor author:Vierkantor	feat(CI): add build output to CI workflows	This PR uses the Zulip build report script (originally developed for the nightly-regression-report workflow) to add a summary of build output to other Zulip posts about workflow results. This allows us to more easily see the origin of a failure. This requires redoing the script a little to make it a bit more flexible, and the output is slightly reformatted to become consistent across the various workflows (4 of them that post to Zulip). We don't do so for the nightly-testing failures, since those run in a different workflow, and it would be a lot of work to access the command output from another workflow. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated merge-conflict CI	55/35	.github/workflows/nightly-docgen.yml,.github/workflows/nightly-regression-report.yml,scripts/zulip_build_report.sh	3	11	['Vierkantor', 'adomani', 'github-actions', 'joneugster', 'mathlib-bors', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot']	joneugster assignee:joneugster	2-10463 2 days ago	2-10464 2 days ago	48-38406 48 days
34491	urkud author:urkud	feat(ContinuousMultilinearMap): generalize some definitions	... from normes spaces to topological vector spaces --- - [ ] depends on: #35430 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	delegated t-analysis	182/112	Mathlib/Analysis/Normed/Module/Multilinear/Basic.lean,Mathlib/Analysis/Normed/Operator/BoundedLinearMaps.lean,Mathlib/Topology/Algebra/Group/Basic.lean,Mathlib/Topology/Algebra/Module/Multilinear/Topology.lean,Mathlib/Topology/Algebra/Module/StrongTopology.lean	5	24	['PatrickMassot', 'eric-wieser', 'github-actions', 'mathlib-bors', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'urkud']	mariainesdff assignee:mariainesdff	1-80072 1 day ago	2-18332 2 days ago	19-31097 19 days
28582	Thmoas-Guan author:Thmoas-Guan	feat(Data): some lemmas about WithBot ENat	Add some lemma about withBot ENat discovered when dealing with `ringKrullDim` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	awaiting-author t-data	58/10	Mathlib/Algebra/Order/Monoid/Unbundled/WithTop.lean,Mathlib/Data/ENat/Basic.lean	2	37	['Ruben-VandeVelde', 'Thmoas-Guan', 'YaelDillies', 'alreadydone', 'erdOne', 'github-actions', 'pechersky', 'urkud']	pechersky assignee:pechersky	14-33269 14 days ago	25-37550 25 days ago	68-1211 68 days
35549	JovanGerb author:JovanGerb	fix(Translate): don't look in arguments of free variables in `shouldTranslate`	This PR addresses a `to_additive` limitation reported at [#mathlib4 > #35179 breaks to_additive call in FLT](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/.2335179.20breaks.20to_additive.20call.20in.20FLT/with/574823087) by making sure `shouldTranslate` doesn't looks at the arguments of free variable applications This PR refactors `shouldTranslate` in a few ways - The monad is changed from `OptionT` to `ExceptT`, with the underlying type changing from `Option Expr` to `ExceptT Expr Unit`. Although this is technically a bit less efficient, it makes the program shorter and more intuitive, because a failure now actually corresponds to a monadic failure instead of a monadic success. - When visiting a `Expr.app` node, we now loop through the whole application at once, instead of doing this step by step and checking the cache at each step. This allows us to detect when the head is a free variable, and skip its arguments. It also lets us deal with `ignoreArgsAttr` more naturally. - This change removes the need for the `inApp : Bool` argument that used to be passed around in order to tell whether a constant was in an application. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/)	t-meta	44/39	Mathlib/Tactic/Translate/Core.lean,Mathlib/Tactic/Translate/ToAdditive.lean,Mathlib/Tactic/Translate/ToDual.lean,MathlibTest/toAdditive.lean	4	5	['JovanGerb', 'github-actions', 'leanprover-radar']	dwrensha assignee:dwrensha	8-74803 8 days ago	12-74679 12 days ago	12-77566 12 days